Use to quickly and accurately measure clearances of rod and main bearings. One 12 inch strip will usually do a complete engine. Place a short length of Plastigauge on the crankshaft bearing journal (about 1/2 inch is sufficient) and then install the bearing shell and tighten the bearing cap (full torque is not required). Remove the bearing cap and shell and measure the width of the deformed plastigauge using the gauge on the package to accurately determine the bearing clearance. Remove the flattened plastigauge residue before reinstalling the bearing shell and cap. Each package contains one 12 inch long piece.