MOST PARTS ARE THE SAME AS THE PARTS FOR THE NEW STYLE 510+ AND 511+ SO WE WILL NOT LIST ALL OF THEM HERE. THE MAJOR DIFFERENCEÂ IS THE VACUUM BREAKERS THAT ARE REQUIRED. THE ORIGINAL 500 BOWLS REQUIRE THE USE OF THE VACUUM BREAKER WITH EXTENSION. THE OTHER PART IS THE BOWL SEALS IF YOUR PORCELAIN HAS A DRAIN HOLE IN IT YOU WOULD USE THE OLDER SEALS WITH DRAIN HOLES 385316140.