These spring covers are suitable for your trampoline:

Pad for 305 cm trampoline
  67,10 
In Stock
Separate spring guard for trampoline, easy and quick to installation, protects against … Buy
Protective Spring Cover for Trampoline inSPORTline Flea PRO 305 cm
  67,10 
In Stock
Protective spring cover for 305 cm Flea PRO trampoline. Buy