Fallkniven CC4 Ceramic Field stone.
Superb honing stone for field use from Fallkniven of Sweden. This is the new CC4 a combination ceramic whetstone for that finest edge, it consists of a super fine white stone (0.1 micron) and a dark grey synthetic sapphire (1.0 micron) these were developed by Fallkniven for their high end knife steels and can create a superb cutting edge.
The compact size (32mm x 100mm) ( 1 1/4in x 4in) makes them easy to carry and field expedient, they also come with a useful leather pouch.
Lubricant is not necessary, though the occasional clean with water and liquid soap would be beneficial.