For removing stiff backnuts and rapid tap installation for 1/2in. BSP and 3/4in. BSP Taps.
Tool stays in position on the tap tail. Uses mechanical advantage of the thread of the tap tail to remove stiff nuts.

Monument Stiffnuts Professional Boxed Kit.
1/2in. and 3/4in. BSP 25mm 27mm nuts 29mm ribbed 32mm nuts. Complete with 3/8in. Cordless drill adaptor, 1/2in. Square Drive; Extension tube and full instructions.