APEM brings additional options to the Q series indicator range, the 16 mm secret-until-lit LED indicator. The Q16 secret-until-lit LED indicators feature a black polycarbonate insert that gives the user the ability to hide a specific custom legend until the indicator illumination is turned "ON." The polycarbonate insert is reverse-side silkscreen printed, allowing for any custom symbol the user requires. This Q16 option also includes a standard rear epoxy-sealed bezel for IP67 protection from harsh environments and rugged outdoor applications.