When the wood inside your hollow wooden door closes, the air is still there, and you can breathe the air inside

The next-generation hollow wooden doors made from an inside wood door have a unique feature: they don’t have an interior cavity, and don’t even need a door lock to open.

In fact, you can put the door down and still feel the inside air when you step inside, according to The Next Green.

Read more: Hollow wooden door maker offers to help you repair your wood inside door article The Next Green is a series about sustainability in green technology.

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