i use the kyosho 46t. it fits real well, never any leaks really with mine. ive been running a custom e-8ight for almost a year now and love it. the only leaking ive had is when i change diff fluid and dont replace the seal and inner o-ring every once and awhile, but thats also just normal maintenence. i can usually get 2-3 changes out of one set. although that 3rd time is starting to get bad though.