Nitrous Pro Flow burst panel spacers serve two distinct functions. These spacers provide the benefits of an open carburetor spacer, but also incorporate our patented replaceable burst panels that will vent pressure between 75-90 psi. for backfire protection with direct port & plate type nitrous systems. Use of this spacer is the only way to meet the requirement by IHRA and other sanctioning bodies for burst panel protection when using a direct port type nitrous system on a cast intake manifold. These light weight spacers are precision machined from billet aluminum with a military spec hard coat for durability and corrosion resistance. Can be used with existing nitrous plate systems. Burst panels are easily replaced within minutes so you can make the next round.