The Cross Dome Family (No Dimple) is designed specifically for mounting on P.C boards & membranes where traces can be fed under the domes. They are placed on a P.C board by adhesive tape. When they are pushed, the center of the dome collapse & make contact. The Cross Dome Family (Dimple) is designed specifically for mounting on P.C boards & membranes where traces can be fed under the domes. They are placed on a P.C board by adhesive tape. When they are pushed, the center of the dome collapse & make contact.