The PRO III 12/8" L-850A,B RCL/TDZ is an 8" runway centerline or touch-down zone light with or without a support ring. It does double duty as a runway centerline light and touch-down zone light. The RCL is a bidirectional light, typically clear/clear or clear/red, with two 48 W lamps. The TDZ is a clear unidirectional light, with a 48 W lamp. RCL/TDZ may be used for any category FAA or military runway.