This is a used Mc Daniel 0-60 boost Gauge in great condition. This is a top of the line Glycerin filled Gauge It is all Brass with a screw on face, not the crack prone leaking cheap stamped sheet metal. I've already done my time with the junk gauges over the years. This gauge fits in a 2 1/8" hole and has a 2 3/8" face outer diameter. The back has 1/8" pipe thread with a 90 Deg. swivel to a 1/4" push lock tube that can be removed if desired. Also has a U clamp and 2 nylon nuts for panel flush mounting. Made in France. Please view my Kawasaki and race parts by typing in drag bike in the search box in sellers other items. Thanks Arnie