These are made of sturdy silicone, but are not self-adhesive so be sure to get some Tensive gel to help keep them in place. Standard square pads with built-in pin connections.
Sizing note: 25mm=1 inch. That makes these just under 2 inches square.
**All pads can be purchased as single sheets or in packs of 3, 5 or 10 at reduced pricing. Larger quantities also available, just ask!