Thanks guys!. Yeah its a boom furler Duncs, discussed earlier in the thread. I have to say that like the chartplotter I have a love hate relationship with it . The chartplotter because its touchscreen in the weather and its little bleeps and and lost position whenever it got wet , but its accuracy was spot on and it was really easy to use.( just make it so you can turn off the touchscreen mr Garmin.) When Dave came back from last years trip they replaced the first unit because of that whole zooming out and flying off to Ethiopia thing whenever it got wet. This new one just bleeped and changed screens a little bit when a splot hit it so it was a lot better. Chart wise as I said , it was smack on for the region we were in in Fiji.
....and the boom because it requires the mainsail to be wound all the way up and all the way down, but it could be infinitely reefed down and all from the cockpit, largely making the trysail redundant.