Crown Bolt 88760 3/8 Inch x 4 Inch Hex-Head Hot Dipped Galvanized Coarse Thread Lag Screws, 25-Count Galvanized 3/8 inch x 4 inch lag screws hex head For wood applications 3/8 inch body diameter and thread pitch 4-inch fastener length Galvanized finish with Rust-Oleum certified rust protection