MC4 connector, a specialized electrical connector commonly used in photovoltaic (solar panel) systems. 

Key Features and Description:

Application: MC4 connectors are designed for connecting solar panels and other components within a solar energy system, facilitating the efficient and safe transmission of electricity. 
Design: They typically appear in male and female pairs, allowing for easy connection and disconnection of solar panel strings. 
Durability: Constructed for outdoor use, MC4 connectors are robust, weather-resistant, and built to withstand harsh environmental conditions, including UV radiation, moisture, heavy rain, and temperature changes. 
Protection: They feature a secure, waterproof design with double seal rings for an IP67 waterproof rating, ensuring protection against dust and water ingress. When properly connected, they are touch-proof, preventing accidental contact with live metal. 
Material and Performance: Often made from PPO material, they offer excellent aging resistance and UV endurance. They typically feature solid copper, silver-plated pin inserts for low contact resistance and high conductivity. 

Specifications (Common):

Rated Voltage: Up to 1000V DC or 1500V DC. 
Rated Current: Typically around 30A or 50A. 
Compatible Cable Sizes: Commonly suitable for 2.5/4.0/6.0 mm² (14/12/10 AWG) solar cables.