ACCU-SYNC spring-loaded flip-up rear sight by Leapers, Inc. / UTG designed for the AR15 platform. Precision machined from aircraft aluminum with a matte black finish. Spring-loaded posi-lock push button activation automatically deploys sight tower and prevents sight tower from collapsing when deployed. Features tool-free windage adjustment and dual apertures, ideal for a variety of different scenarios. Utilizes a single locking torx screw with low profile mounting base and square-shaped integral recoil stops for a secure zero hold and return to zero on MIL-STD-1913 picatinny rails.