Function: Size: 137*77*40cm Solar panel charge controller, 12V/24V, LCD display. All the necessary protections compatible your peace of mind. System tuning parameters. The two USB ports are more convenient. Temperature compensation, dual MOSFET reverse current protection, low heat generation. Solar voltage regulators are designed to meet the needs of the rural electrification market. Afcompatibledable thanks to the latest electronic technology and large manufacturing volumes. This solar controller is suitable compatible 12V or 24V solar system. It has all the necessary protections. Package Includes: 12V/24V 30A Solar Panel Charge Controller LCD Display, Dual USB Ports 137*77*40cm Blue Main Points: 1. The product size is manually measured, there may be errors 2. Due to the as different monitors display different colors, please refer to the actual color you received. 3.Please confirm the size becompatiblee purchasing.