TOUGH LOCK™ Heavy duty retaining head for use with Tregaskiss MIG Guns or Bernard BTB, TGX, T-Gun and clean Air MIG Guns. TOUGH LOCK™ Retaining Heads with Dual Taper Technology are manufactured with a tapered design at both ends that keep your consumables locked from contact tip to neck for improved weld consistency and to maximize heat dissipation, keeping front end consumables running even cooler. Tapers in retaining head create greater surface area contact with contact tip and neck to ensure better heat dissipation and guarantee positive electrical conductivity.