The RB-2 is so great with the added hook. Makes it easy to keep my backpack dry and off the ground, while adding some weight to stabilize the tripod. Amazing how such a simple thing makes all the difference!
This is an excellent way to add a little extra stability to your tripod and I find it really helps in windy conditions. Being universal, this will fit any tripod and attaches securely. I just leave mine attached and fold up the tripod around it so I always have it handy.
The construction seems to be very good and should last a long time. This is such an obvious tripod accessory to own if you experience any stability issues, and is very reasonably priced.