If you pick up a-liter plastic bottles of diameter to one (cut) densely entered second, you get the original expander, exerciser for the muscles of the hands. Adding to the bottom of any of these several holes, you can adjust the force required to compress and stretch. I used the bottle from the water “Darida” and “Berezinsky” turned out pretty well.
A. VINOGRADOV, Mogilev, Republic of Belarus
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