An AR15 style rifle is any lightweight semi-automatic rifle based on or similar to the Colt AR-15 design. The Colt model removed the selective fire feature of its predecessor, the original ArmaLite AR-15, itself a scaled-down derivative of the AR-10 design by Eugene Stoner.
Here we are talking about all kinds of purple beam laser for pistol.
Most of the purple beam lasers for pistol on Amazon is purple laser pens and laser pointers. You can find them here Amazon Purple Laser.
HiLight P3PBL Blue Laser Sight Purple Laser Sight 500lm Flashlight for Pistol Handgun with Micro USB Rechargeable Battery Hard Anodized Aluminum.
Low Profile Green and Purple Duo Laser Sights Sub Compact Pistols USB Recharge on eBay.
Blue ( Purple/Violet ) Beam Laser Gun Sight for Rifle AR15 Pistol on BeamQ.