For the racer that builds an engine everyday or only a couple a year here is an adjustable pushrod diameter checking kit that will take the guess work out of pushrod clearance for your next project. Kit is designed to work with Manton #2700-0030 or #2700-0030A pushrod length kit and very simple to use. Pick from the four diameters of sleeves, slide on pushrod tool, put a supplied O-ring on each end to hold sleeve in place and rotate motor around to check for clearance. Kit includes a handy storage tube, four O-rings and four alum. tubes that measure .437", .500", .562" and .625" outside diameter. Treat yourself and never be a victim of pushrod clearance issues again.