Inner Diameter Gauge

thingiverse

With this device, you can measure the inner diameter of an object. It's especially useful when accessing the area to be measured is through a smaller opening, making it impossible to use a caliper. The length of its legs can be customized using the built-in Customizer feature. To assemble and set up the device, two screws and nuts are required: one M4x10 screw with a regular nut and another M4x12 screw with a self-locking nut.