The Hollow-Set Dropin anchor is designed for anchoring in hollow base materials such as hollowconcrete block and precast hollow core plank. It can also be used in solid base materials. Concrete masonry blocks often have a maximum outer wall thickness of 1-1/2". During the drilling process,spalling on the back side of the wall often decreases the wall thickness, leaving only 1" or less for anchoring. The Hollow-Set Dropin is designed to perform in this environment, where most conventional style anchors will not function properly.