Application:

Sharp Point Tester is used to determinate that points on toys and other articles intended for use by children under 8 years of age, and such points exposed in normal use or as a result of reasonably foreseeable damage or abuse of such toys and articles, present a potential risk of injury by puncture or laceration.

The device has a slot with 0.04 inches width and 0.045 inches long rectangular opening, the two reference sizes sharpness are inserted into the depth of 0.015 inches deep hole of the sensor head. And overcome the spring of 0.5 pound elastic to cause the sensor head to move 0.005 inches again. That was identified as sharp point.