These insulated staples are specifically designed for safe and secure installation of NM (Romex) cable gauges 14/3, 14/3G, and 12/3, and other wire up to 19/32-Inch (15 mm) in width. They are made in the USA and exclusively fit Klein Tools Loose Cable Staplers (Cat. Nos. 450-01 and 450-100). These UL listed staples have a special coating that increases holding power and are available in packs of 300. Other staple sizes are also available from Klein Tools for Romex cables, which is a registered trademark of Southwire Company.