Welded seams and nylon fabric impregnated with thermoplastic polyurethane. Think frogman raft. The straps are also nylon and wider than usual, like seat belts in planes and cars. A wider strap means more Velcro area for better security. The materials we chose cost more but in exchange, you have a seat bag that should last a good long time. All three are slightly roomier than our time proven corresponding sized Uno, Dual and Tubi.

• 33 cubic in, 5 x 3¾ x 2 in
• Sonic welded seams
• Wide 1 ½ in nylon strap with extra velcro
• Fits an MTB tube or two 700c gravel tubes,
plus gas, filler, etc.