Stainless Steel clips have many uses for SCUBA diving. They are most commonly used for attaching various accessories or stage/decompression bottles. Sliding bolt clips/snaps are very secure, easy to operate, and pose little risk of accidentally hooking onto other gear or other entanglement hazards. The 3.5 " and 4" snaps works great for almost anything. The larger 4.75" bolt snap is recommended for use with dry suit gloves or thick neoprene gloves. The smaller 2.75" bolt snap is great for regulators and underwater lights.