The Simpson Strong-Tie® DIAB features improved geometry for smooth and accurate installation into base materials. This displacement-controlled expansion anchor is easily set and features an indication marker to confirm proper placement. The enhanced setting capability of this internally threaded drop-in anchor requires minimum effort for quick and economical installation. DIAB Drop-In Internally Threaded Anchor for 1/4-in. Rod (100-Qty) (Pack of 50000).