Well-suited for all users, our Gatorline Trimmer Line features long-lasting, high-quality materials and fits most standard trimmer heads. .65" diameter trimmer line is an ideal fit for many string trimmer models, including but not limited to: Worx GT Revolution WG170 and WG163, Black and Decker LST136 and LSTE523 and Greenworks 21332. Gatorline is compatible with most standard trimmer heads including fixed-line, semi and automatic bump-feed heads. Additionally, it fits most gas, electric, and battery-powered curved and straight shaft string trimmers. Check your string trimmer manual for recommendations and to ensure that larger lines will work with your trimmer. This trimmer line is packaged in a user-friendly donut which prevents tangles.