BlueSpot 16oz (450g) Fibreglass Ball Pein Hammer The BlueSpot 16oz (450g) Fibreglass Ball Pein Hammer features a soft feel handle for a more secure grip. The fibreglass shaft reduces fatigue and increases shock absorption during prolonged use. The rounded and striking faces are manufactured from drop forged, heat treated hardened steel. Ideal for metalwork. To activate the manufacturers lifetime guarantee, you will need to register the product on the Bluespot website within 30 days of purchase.