7.5inch Coupler Stiffener

Stiffy heavy duty tube coupler stiffiners feature a deep spiral groove for maximum epoxy adhesion. These super heavy duty wall stiffiners are designed to be epoxied inside our cardboard tube couplers to greatly increase their lateral strength. Snapping off a payload at the joint under high speed stress (as occurrs when flying at or near Mach speeds) is not a worry when you fly with a Stiffy.

Coupler stiffeners are also great for joining couplers when used as mandrels.