Cast in many industrial products have long been used mortgages (anchor) bolts with special heads, such that not only pull, but rotate can’t.
With the advent of high strength composite self-hardening compositions that bolt you can “lay” in the body of the finished product (plastic or metal) and making it pre-nest, and then simonaityte.
Recommend to read
THE KNOB UNDER ANY TAP
Even for a small set of hand tools for hand tapping in the holes — you need to have several a ratchet (or one — with several square holes). As shown, more convenient universal — sliding...
FROM FIELDS TO GREENHOUSES
"In the USSR, consistently implemented program of transforming agricultural labor into a kind of industrial— recorded in article 22 of the new Constitution of the USSR. Mechanized, full...