17-4 stainless steel heat treated and precision machined to fit the ODS Adjustable Gas Block, Combo Adjustable Gas Block and the PRO2ACE clamp on adjustable block.
There are 3 variants:
STANDARD- Same as what came with your original block
DIY - 5 1mm (.040") holes plus the blank location
HP - Optimized for high pressure systems like pistols and 556. It's basically the gap between smallest and middle holes, but spread over 5 holes instead of 3.
100% MADE IN USA