The cutting heads that are compatible with this guard are the following:
4002 710 2108 - Mowing Head AutoCut 25-2 - https://www.lsengineers.co.uk/autocut-25-2-stihl-strimmer-head.html
4002 710 2182 - Mowing Head DuroCut 20-2 - https://www.lsengineers.co.uk/catalog/product/view/id/181716
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