Let a buddy use mine and he overstressed it and blew the coupling. Ordered a replacement but got impatient and went to the local hardware. Sized up the broken coupling with 1/4" clear tube and it worked. Still using it that way. The replacement is still hanging with my dremel bit set. That was about a year and a half ago.
ORIGINAL: BillS
I replaced the coupling with 1/4” fuel tubing about a year ago. The tubing does not have splines but the repair was quick and the tubing was in the round things box making it cheap.