ARISAKA DEFENSE Rail Slider Picatinny Rail M-Lok 8 Slot Black. Precision machined 1913 Picatinny rail designed to be used with the Arisaka Rail Slider. Works with all in-spec Picatinny accessories. Features an anti-rotation QD socket at one end and includes standard and short screws to help with clearance around gas blocks or thicker barrel contours.