This DIY pump can be used to inflate a ball, small swimming pool, etc.
It's made from a caulking tube, a PVC pipe, PVC cap, T-Joint, 2 pens and 2 steel balls.
You can get those balls from a bearing.

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Music:
Accralate - The Dark Contenent, Kevin MacLeod (incompetech.com)
Licensed under Creative Commons: By Attribution 3.0 License
http://creativecommons.org/licenses/b...
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