Brother Spool Cap (small) - #130013124 at AllBrands.com
BLACK+DECKER Replacement Spool Cap Part for Single Line Automatic Feed Spool AFS for GH3000 Electric String Grass Trimmer/Lawn Edger RC-080-SF - The Home Depot
Janome Large Spool Cap | 822020503 - iShopTops.com
Amazon.com: Sewable Large Spool Cap for Singer Sewing Machines (2-Pack), R12373210B, Fits Singer 2263, 3116, 3342, 4423, 4452, 8280, and More