TheLeeb Rebound Hardness Test(LRHT) is one of the four most common methods for testing metal hardness. This is the only portable, non-destructive method for determining hardness and is commonly used on pieces larger than 1 Kg, although it may also be suitable for use on smaller pieces as well.
This particular model is very small (~6 inches long) and quite portable. It features an LCD display and on-board electronics to save up to 270 group measurements and can convert between many different hardness standards (HRA, HRB, HRC, HB, HV, HS). The internal battery can be charged via USB (5 VDC).
The D-type probe of this instrument is suitable for many different metals including steel, cast steel, tool steel alloys, stainless steel, cast iron, and cast aluminum alloys.
Relevant standards include:
ASTMA956 “Standard Test Method for Leeb Hardness Testing of Steel Products”
ISO/DIS 16859-1 "Metallic materials - Leeb hardness test - Part 1: Test method"