I just received Hera Arms MPSS kit. It is very interesting approach to safety selector for AR-15 type of rifles with semi-auto triggers. In one kit we have possibility to select traditional, 90 degree safety throw, or use 45 degree short throw. Kit comes with 12 levers and 3 blank caps. Actually there is 4 types of levers and 1 cap, but we get them in 3 colors: black, tan and green. I will install this soon in my HK rifle and report back with results. First glance shows very high quality of parts.
(image from Hera Arms website)