These are the pilot side rudder pedal covers for the Piper Arrow 2 (PA-28R-200). My old rubber ones had the back disintigrate and basically just fell off.
 
These are made from a soft TPU, which feels like a comfortable soft rubber.
 
You don't need glue for these, nor do you have to screw these on. They just easily "clip on".
 
These do not have an STC, so use at your own risk.