Steel gas block replaces factory part using simple tools and helps you fine tune the gas pressure on your Ruger® Mini-14® or Mini Thirty®. Lets you adjust the distance brass flies, reduce battering of the op-rod, and protect optics from excess shock. Improves accuracy by reducing the internal harmonics of the op-rod contacting the receiver during high speed cycling. Adjust from no-cycling for single-shot operation, to wide-open shooting. Sling swivel hole accepts most swivel loops, including quick-detach swivels. Separate models for Mini-14 and Mini-Thirty. Use Mini Thirty model on Mini-14 chambered in 6.8 Rem SPC.