to insert the keys in the front door on a dark landing, and requires some kind of illumination. Well, when a box of matches or a lighter. This problem will not arise, if the door closer to the lock pin miniature flashlight button: fortunately now there are many suitable options fobs illuminated.
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EASY AND CONVENIENT
The voltage is from 1 to 12 In intervals of a single oxen allows to obtain a transformer, the circuit of which is shown in the figure. If desired, the switching is easy to implement...
WITH A SINGLE BLOW
A simple "opener" for metal cans with lacquer or varnish can be done in just a minute from block of wood and two nails.
