The Sci'Con Roller System 2 is the newest version of their Roller saddle bag mounting apparatus. Like its predecessor, the Roller System 2 is easy to use. This is just the mount, an extra for your spare bike so your repair kit will just be a twist away. You'll only need one saddle pack and repair kit -- just shuffle it between the two bikes.
The Spare Roller System 2 saddle mount attaches between the seat rails and stays fixed in place, even when you remove the bag. It's a bit different from the first version. The two tabs that create the "key" have provisions that allow the bag to ratchet tight into the mount, and its dimensions are slightly different. Please Note: It's not compatible with the original Roller System.