- 18mm cooler hose fitting and 0-300'F temperature sender.
- Sized by the outside diameter of the fittings opening end.
- Reads liquid temperature and relays to temperature gauge.
- Mounts anywhere along the radiator or oil cooler hose line.
- Probe measures fluid temps including water, coolant and oil.
- Other in-hose fitting sizes can be found in this eBay listing.