Rooftop Cargo Box That Mounts Directly to T-Slot Crossbars

Updated 10/17/2026 | Published 10/12/2026

Products Featured in This Question

Kuat Varial XL Rooftop Cargo Box - 18 cu ft - Bronze Metallic

$1398.00

Kuat Varial XL Rooftop Cargo Box - 18.5 cu ft - Black - Preorder

$1289.00

Kuat EVA Floor Kit for Varial XL Rooftop Cargo Box - Black

$98.00

Kuat T-Channel Mount Kit for Varial and Varial XL Rooftop Cargo Boxes

$34.64

Question:

I'm looking for an 18 cubic foot rooftop cargo box. My aero crossbars have T-slots, and I'd rather mount the box in those than use clamps underneath. Do you have an option that mounts that way?

asked by: Eric T

Expert Reply:

Hey Eric! Yes, the Kuat Varial XL Rooftop Cargo Box # KU27HR (Bronze Metallic) or # KU48CR (Black) can be channel mounted using the Kuat T-Channel Mount Kit # KU77HR. This replaces the standard mounts and is a great option when oversized crossbars or limited clearance underneath keep the original hardware from fitting. The kit fits most universal T-channels, so we'll want to verify compatibility with your particular bars.

The Varial XL gives you 18 cubic feet of storage, and its front-hinged lid lets you reach your gear from either side of the vehicle or the rear. If you want to add traction to the inside, the floor kit # KU59HR is also available.

What brand and model crossbars do you have?

expert reply by: Robin H

Kuat Varial XL
(click to enlarge)

Eric

10/17/2026

I have Thule WingBar Evo crossbars. I like the idea of mounting directly in the channels instead of having the clamps hanging underneath.

Robin H.

10/17/2026

@Eric the # KU77HR will work great with your Thule WingBar Evo crossbars. It's a nice way to mount the Varial XL without having the clamps hanging underneath the crossbars.