4 Pieces Replacement Spool Cap for Black+Decker Lawn Mowers, Compatible with AFS GH400, GH500, GH600, CST1000, CST2000, NST2018, ST7000, ST6600, ST7700 Trimmer Models. Package Includes: 4 Spool Caps and 4 Springs, Providing Sufficient Supply for Daily Replacement and Storage Needs. High-Quality Materials: Constructed from ABS and Carbon Steel for Durable Performance, Offering Long Service Life, Good Stability, Shock Resistance, Cold Resistance, and Oil Resistance. Unique Design: Specially Engineered to Extend Edge Life on Rough Surfaces; Aerodynamic Structure Helps Reduce Noise and Vibration. Easy to Install: Simple Installation Process, Allows for Quick Replacement and Helps Save on Equipment Maintenance Costs. Ideal for Use in Patios, Lawns, Yards, Gardens, Landscaping, and Around Ornamental Plants; Suitable for Agricultural, Horticultural, and Forestry Applications.