#51806: A heavy-duty 51515 with a built-in standpipe to keep the filter positively full of oil after shutdown in base-down mounting situations (slant-6, for example). These also greatly reduce oil spillage when removing a base-down filter at oil change time, see here and here for more info
#51773: An extra-long 51515 if you want your filter to hold two quarts of oil and have the space for it
#51076: Heavy-duty replacement filter element for factory optional taxi/fleet/police replaceable-cartridge oil filter
#51085: "Super Shorty" Mopar oil filter, 3.79" tall (the 51068 is 4.338" tall, the 51515 and 51806 are 5.18" tall, and the 51773 is just barely shy of 7" tall)
