1. This golf club head weight screw is made of qualified alloy, solid, firm and durable to use, ensures a long time service. 2. The weight screw is made to maintain a good sense of comfort in use for everyone by changing the weight of the head. 3. This aftermarket weight Compatible with M5 Driver Head. 4. 4g,6g, 7g, 8g,10g, 11g,12g,16g are available. 5. Great accessory for Golf players.