Copper Compression Lug, 1 Hole, 400 kcmil Flex, Flared Barrel, 5/8 Inch (15.9 mm) Stud, Can be used with flex conductor class: K, M, and Diesel Locomotive, Flared entry prevents bent back strands when inserting fine strand conductor into barrel, Color-coded barrels marked with Panduit die index numbers for proper crimp die selection, Inspection window to visually assure full conductor insertion, Tin-plated to inhibit corrosion, UL Listed and CSA Certified to 35 KV and temperature rated to 90 Degrees Celsius when crimped with Panduit crimping tools and dies, Tested by Telcordia - meets NEBS Level 3, American Bureau of Shipping Approved.