1.Voltage Rating: Typically, the voltage rating of MC4 3Y connectors is 1000 volts direct current (VDC), making them suitable for photovoltaic systems that generate high voltages.

2. Current Rating: Current rating may vary, but is typically 20-30 Amps (A) per MC4 connection, meaning each connection can safely carry 20-30A continuous current.

3. Material: MC4s are usually made of weather resistant solar grade material, such as fiberglass reinforced polyamide (PA66-GF30). This material is durable and UV resistant.

4. Ingress Rating: MC4 connectors typically have an IP67 rating, which means they are dust and water proof, which is essential for outdoor use.

5. Operating temperature range: MC4s are designed to operate over a wide temperature range, typically -40°C to +85°C, making them suitable for a variety of climatic conditions.

6. Compatibility: MC4 3Y connectors are designed to be compatible with standard solar cables, typically 4mm² to 6mm².

7. Safety: They are equipped with locking mechanisms to prevent accidental disconnection, which improves electrical safety.

8. Durability: MC4s are designed to withstand many connections and disconnections without loss of performance, making them suitable for long term use in solar systems.