The Muffler Hatch is the exhaust of Gregtech Multiblocks.
It must have an Air Block in front of the side with the dot to work. The direction is faces can be changed with an Wrench. Should it be blocked by anything, the Multiblock will work only a single time and then stop until the muffler is freed.
The different levels of Muffler Hatches do not have an effect yet, but it is planned to introduce Pullution to GT, where the different Muffler Hatches will have an effect.
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