The 7378RDS holster is designed to fit and protect handguns with red dot optics. It features the ALS® (Automatic Locking System) retention, an internal locking device that secures the firearm in all directions simply upon reholstering. This ergonomic design features a straight-up draw and the release is completely operable with the thumb, making it very instinctive to use. The 7378RDS holster has an open-top design without SLS for quick retrieval of firearm. This model is constructed of the innovative SafariSeven™ material, a high performance nylon blend. SafariSeven™ is highly durable and practically impervious to the elements. ** Safariland® cannot guarantee that RDS holsters will be compatible with non-factory (Glock MOS, M&P CORE, etc.) mounted red dots.  Numerous variables including depth of RDS into slide, use of dovetail, placement on slide, etc. can all affect the fit of the holster.