Aluminum Butt Hinge, 5" X 5" with 1/2" Diameter Pin, Bolt-on or Weld-onAluminum Butt Hinge, (generally known as a *5" X 5") with a removable 1 2" Diameter Pin Choose Weld On or Bolt on Choose from: no holes drilled for welding applications OR with holes pre drilled for bolt on application This heavy duty trailer aluminum door hinge comes in 3 parts 2 sides and a galvanized steel 1 2" diameter center pin (for strength) with a small hole drilled in the pin at the bottom for a 1" steel cotter pin ( included). Mill finish