Perfect compatibility: 53B heads are compatible with 5018s, 5049s, 5050s, 5762, 5764, 6075cc, 6020s, 6040cs, 6072cc, 6075cc, 6090cc, 7020s, 7025s, 7025s. 071 cc, 71cc 085cc, 7089ccm etc. No matter which one you use, it is easy to buy and replace.
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