This is my second prototype of the 3x3 piston door. It's just 5 x 7 x 9 and it's relatively simple to make. Overall I worked on this door for more than 30 hours but I'm very very pleased with the result. Well unfortunately it's not the smallest ever but still it's quite compact, clean and easy to build :)

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Texture pack: SGYcraft's HD oMega Basics x128
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