For use with Fowler / Trimos Height Gages. Complete Probe Kit includes... Disc-Shaped Insert: 7.7mm Disc-Shaped Insert: 11.5mm Corner Insert 1mm Measuring Insert Holder for: M2.5, M1.6, M1.4 Insert Holder: L=80mm, M2.5 Insert Holder: 90° L=80, M2.5 Ruby Ball Probe 2mm Ball Probe 1mm Knife-Edged Measuring Probe L=88mm Holder with Reduction 8mm / 4mm Swivel Holder: 4 / 8mm Hemispheric Probe Probe with Pin (plus 4 additional pins) Test Indicator Tip: 1mm Test Indicator Tip: 2mm Test Indicator Tip: 3mm Key for Ball Insert 1.5mm Hex Wrench 2.5mm Hex Wrench Includes Case