This brass short flare nut is designed to fit the Mueller NS4-10 flare nut wrench. It is made of brass and has a short flare design. It is a replacement part for the Mueller NS4-10 flare nut wrench. This brass short flare nut is designed to fit the Mueller NS4-10 flare nut wrench. It is made of brass and has a short flare design. It is a replacement part for the Mueller NS4-10 flare nut wrench.