The A-LINE™ M-LH-K2 Insertable Link Block allows the user to align the optical centers of 1-in. and 2-in. A-Line lens mounts. The Link Block has two 6-mm alignment holes spaced 0.50-in.(12.7-mm) apart to align the two sizes of lens mounts. It incorporates an M4 threaded mounting hole for post mounting on Metric SP and MSP Series posts. The slotted guide rod hole can also be used as an insertable post mount for guide-rod-mounted group of A-line lens mounts.