Test Probe Tips are used to connect test equipment to the circuit/chip/design being tested. Often the device consists of a cylindrical rod with a head that is concave, convex, a crown, a clamp, a point or blade, or a hooked end.  The other end is usually a wire lead. The characteristics are tip type, connection type, tip length, overall length, voltage rating, and cable rating (CAT I, CAT II, CAT III, CAT IV, IEC).