This primer base assembly is an important accessory in outdoor lawn and garden power equipment powered by small engines such as chainsaws, lawn mowers, and other small equipment. Since it is made by Zama, it is compatible as a replacement part for small engines of many different brands and models.Be sure to drain any fuel prior to servicing the unit. To replace a damaged primer base assembly, first, loosen the thumb screw. Then, remove the air cleaner lid and the air filter. After that, it's time to remove the air cleaner case. Next, remove the carburetor before removing the primer pump cover plate and bulb. Now the new primer base assembly can be installed and the tool reassembled.This primer base assembly is a genuine OEM part sourced directly from the manufacturer, and it is sold individually. It is an original OEM part sourced directly from the manufacturer, and it is sold individually. It is manufactued by Zama.