Parallels (engineering) — Engineering parallels are rectangular blocks of metal, commonly Instrument metal, stainless-steel or Forged iron, that have 4 or six faces ground or lapped to some specific area end. They can be made use of when machining by using a miller, drill or another… … Wikipedia Перевод: с https://socialbookmarkgs.com/story13999370/a-secret-weapon-for-air-receiver-tank