For Metallic And Non-Metallic Cording And Cable. Easy To Install; Drive Both Zinc Plated Nails Together Without Splitting Wood. Recessed Nail Heads For Minimum Exposure. Smooth Saddle (3/8" Width) Prevents Damage To Insulation. High Grade, Injection Molded Polypropylene Resists Rot, Rust, Deterioration And Effects Of Extreme Temperature; Non-Conductive For Safe And Secure Cable Fastening.