Napa has good stuff & warranties. If it is leaking take it back. That is pretty rare for a new master cyl. to leak. I do like Hoggy say's & rebuild my own unless it's pitted bad. A guy could get bad parts in the kit also though. Iv'e never used SS lines. Did you flare them yourself orwere they factory flares. I use steel lines & usually flare one end myself. The ones I do leak sometimes but the factory ends never do.
