The R7849A,B ultraviolet flame amplifiers are solid-state plug-in amplifiers that respond to an ultraviolet signal from a C7027, C7035, or C7044 ultraviolet flame detector to indicate the presence of flame when used with 7800 SERIES Relay Modules. The R7851B optical flame amplifiers are solid-state plug-in amplifiers that respond to optical signals from C7927, C7935, C7915, and C7962 flame detectors to indicate the presence of flame when used with 7800 SERIES relay modules.