The Sig Sauer ALPHA6 Aluminum Rings are the culmination of testing over hundreds of thousands of units fielded in some of the most unforgiving environments around the world. Through numerous iterations of intensive testing, SIG SAUER's proprietary aluminum alloy provides a highly durable ring system, while being ductile enough to form perfectly around the riflescope without damaging the maintube through proper installation. With the ideal balance of weight and strength, the ALPHA6 system is designed to excel in harsh conditions from the coastal flats to high mountain scree fields. Compatible with 30MM maintubes and various sight heights Machined from SIG SAUER's proprietary billet aluminum alloy Type III flat black hard anodized finish Black oxide hardened steel hardware M1913 / Weaver mount compatible Leveling tool kit provided with all compatible ALPHA6 ring sets Covered by SIG SAUER's Infinite Guarantee