Simpson 3/4" Coil-Thread Drop-In Anchor DIAB75CModel No. DIAB75C Coil Thread Drop In Anchor Coating Material : Zinc Plated Carbon Steel Drill Bit Dia. (in.) : 1 Length (in.) : 3. 125 Rod Dia. (in.) : 3 4 Thread Length (in.) : 1. 25 TPI : 4. 5 Simpson Strong Tie introduces a redesigned Drop In anchor (DIAB) that provides easier installation into base materials. Improved geometry in the preassembled expansion plug improves setting capability so the anchor installs with 40% fewer hammer strikes than