Do not you find that a bunch of keys in your pocket slizhkom became cumbersome? Solder them in pairs, and it will be much more compact and easier to use. The keys are connected to a pair of depending on the length and destination. Possible combinations can be the key to the apartment and from the mailbox; the key of the garden gate, and to give the key to the garage and from the castle at the gate.
Recommend to read
THE SOUND CONFIRMS THE COMMAND
Simple circuits sound LEDs turn on electronic devices In Amateur practice, it is frequently necessary to announce the inclusion of any homemade or industrially produced household...
FLIGHT MODEL FOR BEGINNERS
What is educational flying model? We are all accustomed to the fact that it is a machine fit only to acquire the initial skills of piloting. In most cases, the training model is built...