Plastic circular connectors utilize hyperboloid style contacts

OMNETICS OmneMed line of high quality, plastic circular connectors provide EnduroNest hyperboloid style contacts, incorporating a solid pin that mates with a nest of gold plated wires providing a high integrity electrical interface with low mating force. The reliable contact is highly resistant to shock and able to sustain performance for a high number of mating cycles (100,000 cycles). Devices are ergonomic, easy to handle and suitable for the I/O interface on instrument control units.

http://www.omnetics.com