Red Head Multi-Set 3/8 Inch Setting Tool is a necessary accessory for setting Drop-In Anchors. Anchor is properly expanded when shoulder of setting tool is flush with top of anchor. Typical application of this tool is for HVAC and fire sprinkler use. To set an anchor below surface, drill a hole deeper than anchor length. Thread bolt into the anchor, and then hammer anchor into hole until bolt head is at desired depth. Remove the bolt and set the Red Head anchor with this setting tool.