These are made of sturdy silicone, and ARE self-adhesive, a rare find!. They have built-in pin connections.
Sizing note: 25mm=1 inch. That makes these roughly 2 x 2 1/3 inches.
**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!