Navigation instrument

[oceanpro]

Just looking at the back of a Portland Plotter (still in the packet) & I notice they have listed a Portland Rib plotter. Anyone used one of these? Its not on their website www.blundellharling.co.uk

Is it the a special type which doesn't snap if you sit on it or something?

[John Kennett]

It's similar to a normal plotter, but it's waterproof to IP65 and gyro stabilised. Still breaks if you sit on it though.

John