The spool fits multiple trimmer models: WG150, WG151, WG151.5, WG152, WG153, WG154, WG155, WG155.5, WG156, WG157, WG160, WG160.1, WG160.2, WG163, WG165, WG175, WG180, WG163E.9, WG163E.6, WG163E.3, WG163E.2, WG163E.1, WG163E. Abrasion Resistant: The WA0010 trimmer spool is made of improved polyamide nylon material which has resistance to the pull of more than 100 lbs and is 30% more durable than other brands for a longer lifespan. Efficient Cutting: 12 spool trimmer line WA0004.1/WA0010 String Trimmer, 3 Spool Cover, 30ft 0.065" String Trimmer Line Spool adopts an aerodynamic elliptical shape reduces drag, bendable and flexible, allowing the line to stretch and cushion the impact with hard surfaces, and increases cutting efficiency by 50%, making each spool cut more weeds. Easy to Use: The trimmer spool automatically feeds the trimmer by centrifugal force, reducing the trouble of sorting manually the spare spool while working.