A Slide Caliper Rule in the form of a Bookmark. This is fully dual functional and when not being used as a Bookmark can also be used to measure internal and external lengths or mark angles. It consists of two parts; the main body and the slider blade. The parts are printed separately than joined together by pushing the slider into the main body. Graduations are in millimeters (mm), with intervals at 1, 5 & 10 mm. Maximum length of the scale is 150mm with a usable Caliper length of 130mm. Two jaws are provided one for external and one for internal measurements. The head of the slider has a hole that can be used for hanging the Caliper or a centre marker. Additionally, the head of the slider has both 90 degree and 45 degree angle marking corners. Use a colour that ensures a good contrast with the graduations. However, its possible to infill these with a colour after printing if desired. Assembled dimensions : 71 (W) x 185.5 (L) mm