These Fully Waterproof connectors are available in 2 and 3 wire types.

Gel filled and gas tight these connectors are widely used in the telecoms industry and other fine wire applications. Wires are simply inserted into the housing and crimped down which actuates an insulation displacement mechanism automatically connecting the two wires into an environmentally gel sealed unit.

These are perfect for joins in small 26-19 AWG multi core cables such as wind vanes, sounder transducers, and instruments.
Simply push the wires into the housing (no need to strip the wires first) and squeeze with tight with pliers. 

Housing: Clear polypropylene (UY2),
Wire size: 26-19 awg.