Used great shape Tri Car pump handle, .894 inches inner diameter, wear on aluminum inside and pump screw hole has wear. Single pump arm.
Dimensions are as follows:
Width for the outer diameter where the arm is screwed on (widest point): 1.35 inches
Width for the outer diameter at all points besides where the arm is attached: 1.25 inches
Width inside the ridges: 1.06 inches.
Inner diameter: .89-.895