TUFF-Link couplers are non-metallic high-pressure rated airtight couplings for smooth walled and ribbed HDPE duct and inner duct. The TUFF-Link plastic duct coupler is specifically designed for both press-on and thread-on airtight connections of HDPE duct. It provides a stealthy profile that will not snag on a plow chute. It features high tensile strength plastic with exceptional resistance to side load pressure for maximum durability.