6 Best Alternatives to the SportRack Sidekick Cargo Box (2026)

How alternatives differ from Sidekick

Thule Motion 3 XL Roof Cargo Box

The Thule Motion 3 XL offers 18 cubic feet of storage, more than double the Sidekick’s 8 cubic feet. This extra volume accommodates long skis up to 200 cm and high-volume winter gear. While the Sidekick is compact at 54 inches, the Thule is significantly larger. It targets users needing maximum capacity rather than space-saving. The Sidekick’s 75-pound limit is lower than typical Thule models. If you transport bulky equipment, the Thule provides ample room. The Sidekick remains better for keeping roof profile low. Choose the Thule when volume outweighs aerodynamic efficiency. It is a premium option for serious winter sports enthusiasts who require extensive cargo space on the roof.

Maxsa Innovations 17 cu ft Hard Shell Cargo Box

The Maxsa Innovations 17 cu ft box handles 165 pounds, more than double the Sidekick’s 75-pound limit. This makes it suitable for heavier loads on mid-size SUVs. With 17 cubic feet, it offers double the storage of the Sidekick. The Maxsa is wider at 35 inches compared to the Sidekick’s 25 inches. It is heavier at 35.3 pounds. The Sidekick is lighter and more compact. If you carry heavy gear, the Maxsa provides superior strength and volume. The Sidekick is better for light camping gear. Choose the Maxsa when weight capacity is your primary concern. It sacrifices the Sidekick’s compactness for heavy-duty performance and larger storage space.

Mockins 64x39x5 Extendable Roof Rack Cargo Carrier

The Mockins carrier is a soft bag and basket combo, not a hard shell. It offers 20 cubic feet, more than the Sidekick. The Mockins is larger at 64 inches long and 39 inches wide. It weighs 45 pounds, much heavier than the Sidekick’s 22.7 pounds. It lacks the security of a locked hard shell. The Sidekick provides weather protection and theft deterrence. The Mockins is budget-friendly and versatile. Choose it if you want expandable space and do not mind exposed gear. The Sidekick is better for secure, weatherproof storage. The Mockins suits those prioritizing volume and cost over protection and compact design.

Rugcel Winch 58QT Waterproof Dry Box

The Rugcel Winch is a 58QT dry box, not a traditional roof box. It measures 41 inches long, shorter than the Sidekick. It is narrower at 17 inches. It focuses on waterproof protection rather than large volume. The Sidekick offers 8 cubic feet for general cargo. The Rugcel is ideal for keeping gear dry in wet conditions. It is rugged and rotomolded. Choose it for camping where water resistance is critical. The Sidekick is better for general storage and aerodynamics. The Rugcel sacrifices volume for durability and waterproofing. It is a specialized container for protecting sensitive equipment from the elements during outdoor adventures.

JEGS 18 cu ft Rooftop Cargo Carrier

The JEGS carrier offers 18 cubic feet, more than double the Sidekick. It supports 110 pounds, exceeding the Sidekick’s 75-pound limit. It is 61.3 inches long, longer than the Sidekick. It is wider at 39 inches. The JEGS provides rear access and tool-free installation. The Sidekick has a passenger-side opening. Choose the JEGS for high-volume storage and easier loading from the rear. It is heavier at 35.5 pounds. The Sidekick is more compact and lighter. The JEGS suits travelers needing maximum space and convenience. The Sidekick is better for smaller vehicles and lighter loads. The JEGS prioritizes volume and weight capacity over compact design.

PM Performotor 11 cu ft Hard Shell Cargo Box

The PM Performotor box offers 11 cubic feet, slightly more than the Sidekick. It supports loads under 110 pounds. It is 53 inches long, similar to the Sidekick. It is narrower at 34 inches. The PM Performotor is a hard shell with a textured black finish. It suits drivers with smaller vehicles or limited roof space. The Sidekick is more compact at 25 inches wide. Choose the PM Performotor for a balance of volume and security. It is better for moderate loads. The Sidekick is lighter and more aerodynamic. The PM Performotor offers slightly more space with a similar footprint. It is a solid choice for those needing a bit more room without a large footprint.

Quick picks

Our 7 picks

1 Best overall

SportRack Sidekick Cargo Box

Best for: small loads on most factory racks

Capacity

8 cubic foot

Opening

passenger-side opening

Load Capacity

75 pounds

Security

lock to secure contents

Dimensions

54 x 25 x 15.5 inches

Size

One Size

View on Amazon: SportRack Sidekick Cargo Box

The SportRack Sidekick is a compact 8-cubic-foot roof box for small loads like camping gear or golf clubs. It measures 54 x 25 x 15.5 inches and carries up to 75 pounds. A passenger-side opening makes loading easier, and the included lock secures contents. It fits SportRack systems, square bars, round bars, and most factory racks.

Pros

• 8-cubic-foot capacity suits small loads
• 75-pound load capacity
• Passenger-side opening for easier access
• Includes lock to secure contents
• Fits square bars, round bars, and most factory racks

Cons

• Compact size limits what you can carry
• 75-pound load limit is lower than larger boxes
• Opens from the passenger side only

Good fit if

• You need a compact roof box for small loads
• You want to leave room on the rack for other items
• You want a lockable box that fits most factory racks

Skip if

• You need more than 8 cubic feet of cargo space
• You want to load from both sides of the vehicle
• You plan to carry items heavier than 75 pounds

Verdict: SportRack Sidekick Cargo Box is a compact, lockable roof box that handles small loads well and fits most factory racks. Its passenger-side opening and 75-pound limit make it best for lighter gear.

2 Best premium

Thule Motion 3 XL Roof Cargo Box

Best for: transporting long skis and high-volume gear

Capacity

18 cu ft

Load Capacity

165 lbs

Security

Slide lock

Installation

PowerClick quick-mount

Vehicle Compatibility

Select Thule rack systems

Dimensions

84.7 x 35 x 17 in

View on Amazon: Thule Motion 3 XL Roof Cargo Box

The Thule Motion 3 XL offers 18 cu ft of volume with a 165 lb load rating. Measuring 84.7 by 35 by 17 inches externally, it holds skis up to 200 cm long or three to five snowboards. It suits you if you carry winter sports gear and want a secure PowerClick mounting system with built-in torque clicks.

Pros

• PowerClick mount includes an integrated torque indicator that clicks when tight
• Internal length of 80 inches fits skis up to 200 cm or 3 to 5 snowboards
• SlideLock system provides separate locking and opening functions
• Spacious 18 cu ft capacity supports loads up to 165 lb

Cons

• Long 84.7-inch external length requires significant roof clearance
• Installation requires select Thule rack systems or specific mounting adapters

Good fit if

• You need to carry skis up to 200 cm or multiple snowboards.
• You want a mounting system with an audible click to confirm proper torque.

Skip if

• You drive a small vehicle unable to fit an 84.7-inch box without hatch interference.
• You use crossbars that are incompatible with Thule mounting hardware and lack adapters.

Verdict: Thule Motion 3 XL 18 cu ft Roof Box suits winter sports enthusiasts who need space for 200 cm skis and prefer torque-verified roof mounting.

3 Best 165 lb

Maxsa Innovations 17 cu ft Hard Shell Cargo Box

Best for: Heavy loads on mid-size SUVs

Capacity

17 cu ft

Shell Type

Hard shell

Load Capacity

165 lbs

Vehicle Compatibility

Fits a wide range of cars and SUVs

Recommended Use

Travel essentials, luggage, outdoor gear

Mount Type

Roof Mount

View on Amazon: Maxsa Innovations 17 cu ft Hard Shell Cargo Box

This Maxsa Innovations rooftop cargo box offers 17 cubic feet of hard shell storage with a 165 lb load capacity. Measuring 55.1 inches long and 35 inches wide, it fits most cars and SUVs. The aerodynamic design reduces wind noise and drag. It includes a locking system with two keys for security. You get a practical, weatherproof solution for luggage and outdoor gear.

Pros

• 165 lb weight capacity supports heavy loads
• 17 cubic feet of hard shell storage space
• Aerodynamic shape reduces wind resistance and noise
• Includes locking system with two keys

Cons

• 35.3 lb weight adds bulk to roof load
• 55.1 inch length may not fit smaller roof racks
• No specific vehicle mounting hardware details provided

Good fit if

• You need a high weight capacity for gear
• You have a mid-size SUV with standard roof racks
• You want a secure locking system included

Skip if

• You drive a compact car with low roof clearance
• You need more than 17 cubic feet of space
• You require specific vehicle-compatible mounting kits

Verdict: Maxsa Innovations 17 Cu Ft Hard Shell is a solid choice for families needing heavy-duty storage on mid-size vehicles. Its 165 lb capacity handles bulkier items better than standard boxes.

4 Best budget

Mockins 64x39x5 Extendable Roof Rack Cargo Carrier

Best for: budget shoppers who want a basket and soft bag combo

Capacity

20 cu ft

Shell Type

840D vinyl

Load Capacity

250 lb

Water Resistance

weather-resistant

Dimensions

64 x 39 x 5 in

Weight

45 pounds

View on Amazon: Mockins 64x39x5 Extendable Roof Rack Cargo Carrier

This is a roof rack basket and soft cargo bag bundle. The basket extends from 43 to 64 inches and holds up to 250 pounds. The included 840D vinyl bag adds 20 cubic feet of weather-resistant storage. It suits you if you want a versatile, budget-friendly setup that combines a hard basket with a waterproof bag.

Pros

• Extendable basket length from 43 to 64 inches adapts to different loads
• Includes a 20 cu ft waterproof soft bag made from 840D vinyl
• Holds up to 250 lb, well above typical roof box limits
• Comes with 4 buckle straps, 2 ratchet straps, and a stretchable net for securing gear
• Backed by a 10-year limited warranty

Cons

• Soft bag lacks the hard-shell security and lockable design of a rigid cargo box
• Basket height of only 5 to 6 inches limits tall items
• Assembly of the basket and bag setup required before first use

Good fit if

• You want a budget-friendly cargo solution that combines a basket and a soft bag
• You need a carrier that can hold heavy or oddly shaped gear up to 250 lb
• You have crossbars and prefer an extendable basket for flexible cargo length

Skip if

• You want a fully enclosed, lockable hard-shell cargo box for weatherproof security
• You need a carrier that mounts without crossbars or requires no assembly
• You prefer a streamlined, low-profile design that doesn't add height to your roof

Verdict: Mockins Extendable Roof Rack Cargo Carrier is a practical, budget-friendly alternative to the SportRack Sidekick, offering a versatile basket-and-bag combo with high weight capacity and extendable length, though it lacks the hard-shell security of a traditional cargo box.

5 Best camping

Rugcel Winch 58QT Waterproof Dry Box

Best for: Waterproof camping gear protection

Capacity

58QT

Water Resistance

fully waterproof and dustproof

Security

anti-theft lock compatibility

Dimensions

41" x 17" x 8.5"

Vehicle Type

Car

Recommended Use

Camping

View on Amazon: Rugcel Winch 58QT Waterproof Dry Box

This is a rotomolded PE storage case designed for car camping and off-road use. It holds 58 quarts of gear with external dimensions of 41 x 17 x 8.5 inches. The thick walls provide full waterproof and dustproof protection across extreme temperatures. You get hydraulic rods for quiet opening and a bottom drain valve. It fits standard roof racks for secure transport.

Pros

• Rotomolded PE construction for impact resistance
• Fully waterproof and dustproof seal
• Operates in -40°C to 90°C
• Hydraulic support rods for quiet opening
• Bottom drain valve for easy cleaning

Cons

• Lower volume than 17-18 cu ft competitors
• Requires separate anti-theft lock purchase
• Shorter length limits long gear storage

Good fit if

• You need waterproof protection for sensitive gear
• You prioritize durability over maximum capacity
• You use the box for camping or off-roading

Skip if

• You need to store large or long items
• You require a high-volume cargo solution
• You want a built-in locking mechanism

Verdict: RUGCEL 58QT Rotomolded Dry Box is a rugged, weatherproof container for campers who value gear protection over raw storage space. It suits those prioritizing durability and waterproofing for outdoor adventures.

6 Best 110 lb

JEGS 18 cu ft Rooftop Cargo Carrier

Best for: High-volume storage with rear access

Capacity

18 cubic ft.

Shell Type

HDPE plastic hard shell

Opening

rear

Load Capacity

110 lb.

Water Resistance

weather-tight seal

Security

four corner locking system, front latch

View on Amazon: JEGS 18 cu ft Rooftop Cargo Carrier

This JEGS hard shell carrier offers 18 cubic feet of interior space with a 110 lb load capacity. It measures 61.3 inches long and opens from the rear for easy access. The HDPE plastic shell features a weather-tight seal and a four-corner locking system. It weighs 35.5 pounds and installs without tools. This unit suits drivers who need secure, weatherproof storage for gear during travel.

Pros

• 18 cubic feet of interior capacity
• 110 lb maximum load weight
• Rear-opening design for easy access
• Weather-tight seal for protection
• Tool-free installation process

Cons

• 110 lb load limit is lower than competitors
• 35.5 lb weight adds vehicle drag
• No mention of aerodynamic fuel-saving features

Good fit if

• You need high-volume storage for bulky items
• You prefer rear access for loading gear
• You want a tool-free installation setup

Skip if

• You frequently carry loads over 110 lbs
• You require the highest possible weight capacity
• You need a carrier with advanced aerodynamic claims

Verdict: JEGS 18 cu. ft. Rooftop Cargo Carrier provides ample space and secure locking for travelers who prioritize volume over maximum weight limits. It is a solid choice for those who need easy rear access and simple installation without tools.

7 Best 11 cubic feet

PM Performotor 11 cu ft Hard Shell Cargo Box

Best for: compact loads under 110 lbs

Capacity

11 Cubic Feet

Shell Type

ABS plastic

Opening

opens to 14" wide

Load Capacity

110lbs

Security

key and lock

Installation

tool-free or simple installation

View on Amazon: PM Performotor 11 cu ft Hard Shell Cargo Box

This PM Performotor cargo box offers 11 cubic feet of storage in a 53-inch hard shell. It features a textured ABS plastic exterior and a 110-pound load limit. The unit opens 14 inches wide for loading bulky items. You get a keyed lock system for security. It mounts to crossbars with included brackets. This is a practical option for those needing moderate, secure rooftop storage.

Pros

• 11 cubic feet internal capacity
• 110-pound maximum load limit
• 14-inch wide opening for loading
• Keyed security lock system
• Textured ABS plastic hard shell

Cons

• 110-pound capacity is lower than competitors
• 11 cubic feet is smaller than larger alternatives
• 53-inch length may not fit narrow roof racks

Good fit if

• You need a compact 11 cubic feet storage solution
• You have roof racks with limited width
• You want a hard shell with a keyed lock

Skip if

• You require more than 11 cubic feet of space
• You need to carry loads over 110 pounds
• You prefer a glossy finish over textured black

Verdict: PM Performotor 11 Cu Ft Hard Shell is a compact storage solution for drivers with smaller vehicles or limited roof space. It suits those who prioritize security and a moderate load limit over maximum volume.

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