Trampoline spring 138mm, D25x3,2mm. Broken trampoline springs can be replaced one by one. We recommend replacing all springs at once if you are replacing a worn jumping mat with a new one. The springs are suitable for HOME 4 YOU trampolines with codes 90406 (D304cm / 64 spring), 09410 (D366cm / 72 spring) and 09413 (D426cm / 88 spring).