3.5吋彈簧 - 直徑20公釐 - 數量6

Wasn't sure a 20mm spring would fit, but they slotted right in and feel sturdy. Six in the pack meant I had spares for the rest of the set, and the coils held up fine after a few weeks of daily use.

Swapped these into my trampoline after the old springs got stretched out, and the 3.5" length matched up fine. The set of 6 was just enough for one side, though I wish they came in bigger packs so I could've done the whole frame at once.

These fit my old trampoline frame perfectly and the 20mm diameter matched the originals. Only grip is the set of 6 was one more than I needed, but the springs feel sturdy and passed the bounce test fine.