PRP Welch Plug Fitting Kit - Toyota 1JZ/2JZRB Direct replacement Welch Plugs Freeze Plugs Expansion Plugs. These high quality Australian made plugs are used in many high performance street and race applications, many of the big drag cars here in Australia use these and are a testament to their quality. Brass is renowned for it's anti corrosion properties whilst still retaining its tensile strength, this means it will survive a long way beyond your engine build. These come as a complete bottom