Specification Brand : HARFINGTON BulletPoint1 : Size - 1000mm 39 inch inside caliper and outside caliper. BulletPoint2 : Material - Our firm joint calipers are forged from 410 stainless steel, with overall heat treatment, micro-magnetic, corrosion-resistant, high hardness, high torque, and good toughness. BulletPoint3 : Feature - Smooth surface and burr-free, accurate measurement, can be used for a long time and not easy to loosen. BulletPoint4 : Application - Outside calipers measure the external size, thicknesses and outside diameters of objects. Inside calipers measure the inner diameter or groove width of the cylindrical hole. BulletPoint5 : Usage - Firm joint caliper use friction joint to hold the legs not move, adjust a caliper to a scale dimension, one leg of the caliper should be held firmly against one end of the scale and the other leg adjusted to the desired dimension. ItemName : HARFINGTON Firm Joint Inside Outside Caliper Set 1000mm 39 Inch 410 Stainless Steel Firm Friction Joint for External Internal Measurements ItemPackageDimensions_Height : 2.36 inches ItemPackageDimensions_Length : 40.16 inches ItemPackageDimensions_Width : 14.17 inches ItemPackageQuantity : 1 ItemTypeKeyword : joint-calipers-and-dividers Manufacturer : HARFINGTON Material : Stainless Steel PartNumber : hta240319hh000864 ProductDescription : 1. 1000mm 39 inch inside caliper and outside caliper. 2. Our firm joint calipers are forged from 410 stainless steel, with overall heat treatment, micro-magnetic, corrosion-resistant, high hardness, high torque, and good toughness. 3. Smooth surface and burr-free, accurate measurement, can be used for a long time and not easy to loosen. 4. Outside calipers measure the external size, thicknesses and outside diameters of objects. Inside calipers measure the inner diameter or groove width of the cylindrical hole. 5. Firm joint caliper use friction joint to hold the legs not move, adjust a caliper to a scale dimension, one leg of the caliper should be held firmly against one end of the scale and the other leg adjusted to the desired dimension.