A Probe tip into one easy-to-use double-end instrument. All Wise Probe tips are made from spring- tempered stainless steel and machine ground to exacting tolerances. The millimeter measurements are precisely cut into the Probe tips. Color- coding is applied to probes under extreme temperatures so that the color penetrates the surface of the tip. Probe tips undergo additional tight- tolerance grinding to achieve the desired readability for each marking. All tips are then formed by hand into their final shape by expert craftsmen.