Simpson CSD25400MG 1/4" X 4" Countersunk Head Split-Drive Anchor - Galvanized, Pkg 100 Quik Drive Cement Board Screws Simpson flat head type 316

Simpson flat head type 316 stainless steel screws are designed to fasten securely in fiberglass

they drive fast and pull materials tight without the need to pre-drill

these screws also enhance the look of your project by blending with wood tones

these collated screws are built for speed

Self-Drilling Point: Eliminates the need for pre-drilling by cutting directly into metal substrates for faster installation

Simpson CSD25400MG 1/4" X 4" Countersunk Head Split-Drive Anchor - Galvanized, Pkg 100 Quik Drive Cement Board Screws Simpson flat head type 316The Split Drive anchor is a one piece expansion anchor that can be installed in concrete, grout filled block and stone. As the anchor is driven in, the split type expansion mechanism on the working end compresses and exerts force against the walls of the hole. The Countersunk head allows for a smooth surface when attaching wood or light gauge steel to concrete and grout filled block surfaces. Installation: For Common Rafters: Drill a hole in base