These are hard plastic, and they connect your breather hoses together. Most often they can be reused.
They can often be reused if you carefully cut the hardened rubber away from the coupling. If you prefer new here you go. Three are included here and that is the total used on your V6 or V8 engine up through 2006.
M112 V6 M113 V8 Breather Hose Plastic Couplings x 3
$12.00
SKU:
GEG-112BCOUPLINGS 
Product Details
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$44.50
M112 V6 M113 V8 U.S ( Not AMG or Euro Spec ) Breather Hose Replacement Kit w/ Video Instructions
PLEASE READ CAREFULLY: WILL NOT FIT AMG ENGINES. Kit includes 4 new breather hoses. Free rubber manifold connector and silicone included. LITTLE CONNECTORS NOT INCLUDED - originals can be used or you can purchase separately.
For most U.S. V6 and V8 engines from 1998 to 2006 with mass air flow sensor at the back center of the engine.
WILL NOT FIT AMG ENGINES.
$9.80
M112 V6 M113 V8 Breather Hoses to Manifold 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.
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.