Well-made rubber (ThermoPlastic Urethane) insulators for the Perfect Balance Pedal hoop clamp... two outer and two inner for the upper clamp, and two outer and two inner for the lower clamp.
Anyone that frequently detaches and reattaches their PBP for gigging, etc. soon realizes these rubber insulators begin to deform and ultimately the outer and inner pieces separate and get lost. The two pieces are only attached to each other by compression so extra care must be taken during pedal removal and installation.
Fortunately Thomann makes them readily available, but a better design would minimize frequent replacement or even eliminate it. To help improve their longevity, I currently apply Super Glue Gel to the center of the outer and inner pieces when assembling which provides a stronger bond than just compression.
Hopefully Sonor will improve this design in future versions or pedals.
NOTE: The current Thomann product title of "* TPU Puffer Set" is most likely just a typo of "* TPU Buffer Set".