Depending on the age and mileage of your V6 or V8 engine, this part may or may not need to be changed when you replace the breather hoses. You can check before ordering. If the part is still soft and rubbery, then it most likely can be reused. If it is hard, you will have difficulty connecting your new breather hoses to this connector.
4 breather hoses connect to this rubber must-connector at the rear of the intake manifold. Instructions are included with the 4-hose replacement kit.
M112 V6 M113 V8 Breather Hoses to Manifold Connector