Check the listing for details. Spool & Line For McCulloch MT21 Strimmer Grass Trimmer. Color: Blue, Condition: New. Listed at 14.73 USD. This can be due to the manufacturer changing suppliers during or after a production run of the appliance. Usually the part may only differ visually by colour but fits just the same. In some cases the manufacturer may have experienced problems in the field and has upgraded the part to prevent a repeat of the early failure of the part, but again should fit the same as the original. There are occasions where a part has been modified and additional alterations may be needed to the appliance for the part to fit, but on these occasions the manufacturer usually supplies release notes and diagrams along with the part to help aid installation. We take great care packing every item to ensure safe shipment to you. We post daily Monday to Friday with the aim to have your purchase arrive within the e.