Starrett HT-1300-01 Test Block, For 3811A Leeb D Test Block 3811A

The Starrett HT‑1300‑01 is an official Leeb D hardness test block designed specifically for calibrating and verifying the performance of Starrett 3811A and 3810A portable hardness testers. This block provides a certified reference hardness value for checking the accuracy of D‑type impact probes, ensuring reliable and traceable hardness measurements in the field or laboratory.