I've just got a new strobe - this is an interesting idea - this unit combines a strobe and an LED torch, so two important safety items are combined into one. Runs on 3 x AA batteries and the box says it's waterproof to 40 meters and the strobe is said to be visible up to 5km on land and 25km from air to surface.
Not having been able to test that, I can't comment but it does work well as far as I can see. The one I have comes with a cord and slider which seems to be intended to attach to your wrist. By modifying a velcro strap a little, I was able to mount it on my BA shoulder straps using the slots on the side.
It seems a solid bit of kit and if you are prepared to trade off the fact that it's a little bulky at 14 x 5cm (and fairly heavy ) against the benefit of combining two bits of kit into one, it would be worth considering. In "torch mode", it's adequate for general use but the beam is more flood than throw.
It's made by Xenec and seems to be fairly readily available from diving shops and eBay. Be careful, as there are similar versions which only have an ordinary bulb in the torch - they are a bit cheaper though.
The whistles are seriously loud, available in black or orange and can either be tied or clipped to a BA strap. Everyone should have one of these.
Mike Buckley - October 2004