XS R3D 2.0 night sights with green or orange dual-illuminated front sight are now available for Glock pistols with A-CUT. These Glocks allow direct mounting of the Aimpoint COA red dot optic, and the extremely low profile of this R3D 2.0 sight (in the lower fifth of the optic window) results in minimal visual obstruction, making it an effective backup sight if the optic fails.