Improve Efficiency - Solar are mainly used to optimize the output power of solar p ovoltaic panels to that the system can work at maximum efficiency. Solar optimizer can significantly increase system power generation by 5-25% Durability and Compatibility - P ovoltaic optimizer is made of material, which is wear-, and - and Almost Compatible other of p ovoltaic panels. Simple Installation - Just connect the input end of the solar panel optimizer module to the output end of the p ovoltaic module to convert the small current into a large current. The installation is convenient and simple. Note:If the appearance is slightly different, it not affect the use. Colour:Black Material:Plastic Package Contents: 1 * MPPT Power Optimizer Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.