Cambelt tensioner to suit Ford Zetec Black top 1.6/1.8/2.0 and the ST170 RS Focus engines. This is similar to the WRC Focus item. This replaces the std plastic sprung loaded item to allow constant tension via eccentric adjustment. Unlike the std item which allows cam timing to vary up to 5* over 7000rpm. Straight forward replacement, no other parts required. Uses 316 stainless steel ecentric hub with 2 high quality roller bearings with cnc machined alloy belt roller circliped together for replacement of bearings if need be. Ideal for high rpm rally or race engines. Comes with fitting bolt and washer.