AmeriGlo suppressor height sets provide an elevated sight picture, able to co-witness with slide-mounted miniature red dot optics and suppressors. This flat black sight set is designed for use on Glock MOS pistols. Provides Lower 1/3 co-witness using the Aimpoint ACRO and Holosun 509T optics and Lower 1/4 co-witness using the RMR,SRO, Holosun 407C, 507C, 508T. For more information on how to choose the correct height set for your suppressor or optic, visit the AMERIGLO website, under the INFO tab.