<p>These metering orifices control fuel flow into the metering system. They are rated in flow capacity cubic centimeters per minute and are changeable for tuning purposes. The shape of the entry, exit, and size determines flow. All holley main jets are flow tested and then stamped with the correct number</p> <b>Features</b> <ul> <li>Improved jet extension design that actually screws into the metering block</li> <li>The installation effectively moves the fuel entry point for the main jet out into the fuel bowl</li> </ul> <b>Specification</b> <ul> <li>Compatibility: holley performance carburetors</li> <li>Hole size - 0.25 in.</li> <li>Thread size - 0.25 in. - 32</li> <li>Jet extension style - Screw-in</li> <li>Material - Brass</li> <li>Quantity - Set of 2</li> </ul>- SKU: KSAO64973