UniversalChain 40 (3600HB8101). UniversalChain 40 (3600HB8131). UniversalChain 40 (3600HB8171). UniversalChain 40 (3600HB8400). UniversalChain 40 (3600HB8430). This can usually be found on the base, side or back of the chainsaw.
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