SLEDGE/CLUB HAMMER FIBREGLASS SHAFT Double faced sledge hammers are fully forged and heat-treated. Ideal for use on spikes, stakes, cold chisels and hardened nails. They are available with a hickory or fibreglass shaft. Fibreglass Shaft (BS 876 Sledge Hammers) Dampens the impact transmitted to the user?s hand and wrist. Tested to the requirements of BS 876: 1981 (head stamped BS 876).