Use this kit to attach an oil pressure gauge to your Model A. Kit contains 5' of COPPER tubing, not plastic, elbow fitting for attaching to motor, and a straight fitting for attaching to the gauge. On a Model A, you remove the A-6621 oil pump hole plug and replace it with the male threaded fitting in this kit. The oil pump oil plug is the slotted pipe plug on the side of the block (middle) between the oil pan and the valve cover.