The CycleAware Beamer Reflective Saddle Bag has something I’ve always though other bags should have, i.e., a highly reflective case. I have several saddle bags with small reflective strips, but this bag is made entirely from reflective material.
I put the CycleAware Beamer Reflective Saddle Bag on the road bike I use for night rides and riding in the rain. The bag is small (6″ X 3 1/4″ X 2 1/2″) and is just big enough to hold a spare road tube, patch kit, two tire levers, a CO2 inflator nozzle with two cartridges, and a Topeak 9 Mini Pro tool. This bag attaches under the saddle itself with a sturdy strap, but is not attached to the seat post with Velcro straps like most saddle bags.
While this bag is perfect for a road bike it would be too small for a mountain bikes because there would not be enough room for the larger mountain bike tube (I tried). I really wish CycleAware offered a slightly larger bag. My only complaint with this bag is that it does not have a loop so you can clip on a reflector or flasher. However, since this bag fits tightly under the saddle you should have room to attach a flasher on your seat post.
The CycleAware Beamer Reflective Saddle Bag has a retail price of around $25. If your local bike shop does hot carry it you can always find one at Amazon.com.