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
A GOOD TRACTOR
A. Lomakin from the city of Artem of Primorski territory considers that the design of his tractor pretty good, as is relatively simple due to selection (albeit random) units. The frame...
TRANSPORT FOR THE TWO ELEMENTS
Nikolay Ilyich Kamov Is... to say it as I see numerous helicopters created under the guidance of this famous aircraft. This baby Ka-10, able to fly right out of the body "three-ton", and...