DDI SPORTS Trampoline Part Store 5.5" inch Ultra-Grade Trampoline Springs, Quantity of 12, Extension Spring, Farming, Ranching, Machinery, Maintenance, Home Repairs steel Imported QUANTITY: 12- per pack- 5 1/2" Trampoline Extension Springs, Farming, Ranching, Machinery, Maintenance, Home Repairs TOP QUALITY: (28-Coils) Trampoline Springs made for the Ultimate- Extreme- Bounce!! DIMENSIONS: Outside Diameter of the Springs are 1", we use 8-ga. High Tenacity Steel Wire, The Wire Diameter of our Springs is 0.125 of an inch thick. The Measurement is Over The Hook WHAT SIZE DOES IT FIT: Any Trampoline requiring the specific Spring Length shown, Plus or MINUS up to 1/4 inch ASTM, EN 71, TUV & GS SAFETY APPROVED - ASTM is the Safety Council for America - EN 71 is Europe - GS & TUV is Germany