This series of pushbutton switches and indicators are used for automation and signals in control circuits below AC250V, DC110V with frequencies of 50Hz or 60 Hz The functions and features: 1) The diameter of the installation hole of the series pushbutton: 16mm 2) Use either the gold-clad silver contact or silver contact 3) The front shape: round (F18mm), rectangular (18 x 24mm), square (18 x 18mm) 4) Many types are available: pilot lamps, pushbuttons, illuminated pushbuttons, selector switches, and key lock switches 5) IP protective degree: IP40, IP65, IP67 6) The front color: red (R), green (G), yellow (Y), amber (A), blue (BL), white (W), black (B) 8) The black cover can't be used with the illuminated pushbuttons