What's a better version of the classic Seat Pack? The result is the Seat Pack XT. The XT has Timbuk2's signature wide-mouth opening for quick and easy access, blinky light attachment and reflective hits for safe night riding, plus waterproof accents and a new attachment system. The bungee seat post attachment is a synch to use and the accompanying SR buckle makes it easy to attach to rails and adjust until you're comfy. You'll want to ride it everywhere.