Self-drilling no pre-drilled hole required. Higher load-bearing capability and screw size range than other self-drilling drywall anchors. Built-in "positive-stop" prevents over-driving the anchor when using a screw gun or hand drill. Activate and lock with an audible "POP", providing positive feedback that they are installed correctly. Resist vibration and shock. Provide high pull-out resistance. Do not back out of the wall when the screw is removed. Can be removed easily, without damaging wall. Unique tip prevents "walking" to ensure accurate and easy drilling. When activated with a screw anchor opens with an audible pop locking the anchor on the wall. Drywall gypsum and its paper are kept in compression and thereby immediately reinforced. Built-in positive stop that prevents overdriving the anchor when using a screw gun. 20 pack Regular SnapSkru 3/8" - 5/8" drywall thickness #8 x 1-1/2" combo screws 1-1/4" + thickness of item being anchored #6, #7, #8 (preferred), #10 Self-drilling no pre-drilled hole required Regular: 0.62"dia. head, 5/16" dia., 1-5/8" length Higher load-bearing capability and screw size range than other self-drilling drywall anchors Built-in positive-stop prevents over-driving the anchor when using a screw gun or hand drill Activate and lock with an audible POP, providing positive feedback that they are installed correctly Resist vibration and shock Provide high pull-out resistance Do not back out of the wall when the screw is removed Can be removed easily, without damaging wall Unique tip prevents "walking" to ensure accurate and easy drilling When activated with a screw anchor opens with an audible pop locking the anchor on the wall Drywall gypsum & its paper are kept in compression & thereby immediately reinforced Built-in positive stop that prevents overdriving the anchor when using a screw gun.