SPI Z9009 4-8in Caliper Centerline Gage Attachment

The SPI Z9009 is a new caliper centerline gage attachment sold as a 1-piece set (two matched pointed bodies plus a hex key), designed to convert a standard 4", 6", or 8" dial or vernier caliper into a center-to-center distance measurement instrument. Each hardened steel body features a precision-ground conical point and a longitudinal slot with two set screws (tightened with the included hex/Allen wrench) that clamp firmly onto the caliper jaws, seating flush so the pointed tips align along the caliper's measuring axis. The slot width is 0.141" (3/6" per the instruction sheet, matching the jaw thickness of 4–8" calipers), distinguishing it from the Z9010 variant (0.5" slot for 12" calipers). To obtain the true center-to-center measurement, the user adds the combined outer diameters of the two bodies divided by two to the caliper reading, per the included instruction sheet (part numbers Z9009–Z9010 listed). Compatible with any 4", 6", or 8" dial or vernier caliper with standard jaw geometry; not designed for digital calipers with non-standard jaws.

Product Specifications