When used within a SOFT CASE this thick piece of 3/4" neoprene rubber sits above your pedalboard and gives an extra layer of bump protection to the knobs and footswitches of your pedals. Along with the solid bottom and sidewalls of the pedalboard, this allows for nearly 360 degree protection in a lighter package than hard cases. It also makes for a very comfortable surface against your body when using the shoulder strap, and points the solid walls and rubber feet of the pedalboard outward.