This Chip on Board COB Led Light is a very small and innovative product, it comes in many different Shapes and Sizes. Its mostly used where the thickness of the product is a very important consideration. This led comes with an aluminium metal back which acts as a heat-dissipating area for the Led, as these led got hot while running, but for the safety purpose we will recommend you to attach a metallic heat sink with it or paste it on the metal surface. Input Voltage:- 3.7v – 4V. Max Input Voltage:- 4v (More than 4v Voltage will completely damage the product ) Aluminum back as a heat sink.   Package Includes: 1 x 3.7v – 4V Ram COB led Light [ Color – Cool White ]