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World of Engineering
@engineers_feed
The most fun way to learn something new everyday.
参加 August 2015
69 フォロー中    3.5M ファン
Fill-level indicator for gas cylinders. It sticks magnetically to common steel propane or butane bottles and uses ultrasound to check whether liquid gas is present at that height. Green means gas is still there; red means the liquid level is already below the sensor. You slide it up and down the bottle to find the fill line.
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