Abstract: An injection apparatus has a jacket having a front end and a cartridge for containing a liquid having a rubber membrane closing a front end of the cartridge at the front end of the jacket. A double-ended needle is held in a needle holder such that both ends thereof are exposed and oriented, one end at the membrane for piercing the membrane to obtain the liquid from the cartridge, and the opposite end for injecting the liquid. First cooperative threads on a cap and the jacket are for screwing the cap onto the jacket and unscrewing the cap therefrom, the first cooperative threads having a first pitch and a first rotational hand.

Abstract: For the purpose of securing a thin, enamelled wire (15) to a tubular plug pin (10), whose one end is embedded in a massive block (14), the wire (15) is clamped in the pin (10) by means of a plug (16) which is conical at both ends and may thus, no matter how it faces, be forced into the pin (10) to clamp the wire (15) to a flattened state there so that its enamel bursts, which provides an effective electrical contact.