Ideal for triathletes, TT riders and endurance road or gravel riders who want a neat top tube box for nutrition and small essentials with either bolt-on or strap mounting.
The Profile Design ATTK XL is a hard-shell top tube storage solution built for riders who want quick access to nutrition without the wobble and bulk of a traditional soft bento bag. The shape is long and narrow, so it sits cleanly behind the stem, and the flexible upper design makes it easier to grab gels or small essentials while you're riding.
What makes this one especially practical is its dual mounting setup. If your bike has top tube braze-ons, you can bolt it straight on for a cleaner fit. If it doesn’t, the supplied FPS straps let you mount it to a much wider range of bikes instead. The shell is also designed so cables can pass straight through to the top tube, which is handy on bikes with front-end routing that can clash with some storage boxes.
For triathlon, TT, gravel and fast endurance road setups, this is a smart choice when you want aero-minded storage, a more secure feel than a floppy fabric bag, and a shape that stays tidy on the bike. It is not the biggest option in the category, but that’s also the point: you get enough room for ride fuel and small essentials in a package that stays sleek, stable and easy to live with.
Slim aero-style profile
The long, narrow shape sits neatly behind the stem to keep storage tidy and low-bulk on race and endurance setups.
290 cm³ storage capacity
Big enough for gels, bars and small ride essentials without moving to a much larger bikepacking-style bag.
Bolt-on or strap mounting
You can fit it to bikes with direct-mount top tube bosses or use the supplied FPS straps on frames without them.
Cable pass-through shell
The shell design allows cables to route straight through to the top tube, helping it work better with bikes that have front-end cabling in this area.
Easy-access upper design
Flexible materials and large cut-outs make it easier to open and reach contents while riding.
Hard-shell stability
Compared with softer fabric bags, the moulded construction gives a more structured feel on the bike.
Protective mounting hardware included
It comes with FPS straps, bolts, a divider, gasket and frame protection strips, so you have what you need for either mounting approach.
General
Dimensions & weight
Compatibility
Features
What's included
Care
Warranty
ATTK
This aero top tube storage design keeps your ride essentials tucked neatly behind the stem, helping you carry more without adding a bulky shape into the wind.
Frame Protection System (FPS)
FPS straps let you mount the case on bikes without direct-mount bosses while helping protect your frame from zip-tie rub and scratches.
Great for
Maybe not for
Check that you have enough clear top tube space for the 305 mm length, especially on smaller frames or bikes with a very short head tube area. It mounts via two top tube bosses on compatible frames or with the supplied FPS straps on bikes without bosses. If you use straps, adding clear frame protection film is a sensible extra step to help protect paint.
vs Apidura Racing Bolt-On Top Tube Pack (1L)
The Apidura is lighter, larger and built around a waterproof welded soft-pack design with a magnetic flip-top, while the ATTK XL goes for a lower-volume structured shell and broader mounting flexibility.
vs Topeak FastFuel TriBag
The Topeak offers more storage and a traditional soft-bag format with internal organisation, while the ATTK XL is narrower and more purpose-built for tidy race-day nutrition storage.
vs XLAB Stealth Pocket 400c
The XLAB is another slim aero-minded nutrition bag, but it is strap-mounted only and uses a zipped soft construction. The ATTK XL gives you a harder structure and a direct-mount option.
Best when you know exactly what you want to carry
This style of box makes the most sense for ride fuel, a small multitool, cash or similar compact items. If you need to carry bulky spares or a larger phone plus extras, a larger soft top tube pack may suit better.
Check stem-to-boss position before buying
On bikes with top tube bosses, the box length matters more than capacity. Measure the clear space behind the stem and check for headset top caps, cable loops or frame shapes that could interfere.
Direct mount gives the cleanest result
If your frame has the right bosses, bolting it on is the tidiest setup and avoids strap wear on paint. The strap option is useful if you want the same box on more than one bike.
A structured box feels neater on fast bikes
Compared with soft fabric bags, a moulded design usually keeps its shape better and looks cleaner on triathlon, TT and aero road setups.
Cycling components designed for speed.
Profile Design is a cycling components brand best known for products aimed at speed-focused riding, especially in triathlon and time trial. Since 1988, the brand has built its name around aerobars, hydration systems, wheels and storage solutions designed with an emphasis on aerodynamics, fit and adjustability.
The brand is widely associated with performance-oriented cockpit and storage products that help riders refine position, control and on-bike setup. Its range centres on practical equipment for athletes and riders who want organised, race-ready bikes with a strong focus on function.
