The Faithfull G-Clamp is built to resist distortion, the ribbed frame is manufactured from malleable SG iron making these clamps virtually unbreakable.The spindle has acme cut threads to provide a smooth operation and maximum clamping pressure.The frames have a powder coated finish for increased resistance to corrosion making them suitable for a wide variety of metalworking and woodworking applications. Ref: UTTK10926