The Samson Aluminum Splicing Fids Set includes four different sizes to meet various splicing needs: ½" / 12mm, 7/16" / 10mm, 5/16" / 8mm, and ¼" / 6mm. These high-quality splicing fids from the trusted brand Samson are essential tools for boat owners and mariners looking to securely splice anchor and docking lines. Each fid is designed to efficiently and effectively splice ropes and cables, making it a valuable addition to any boat parts collection.