20 x Auto self Flash LEDs 3mm Red without extra circuit Frequency = 1 second

Buy It Now Price is for 20 pcsFlash Automatically Every one SecondNo Need Of extra circuit3mm RED LEDsSuitable to simulate police wagon, ambulance, fire engine and other alarm system.    Characteristic U = 1.9 - 2.2VI = 15 - 20mAPrice is for 20 unitsWill Flash every one second. Cathode 16mm Anode 17mm Long.Brand newPRODUCT  DESCRIPTION Use these LEDs to make alarm system or singals etc...the LEDs may flash automatically when connect to power source....