The XDeep Open SMB is simply a 130cm long tube that is open at one end so that it can be inflated using an regulator, exhaled bubbles or other means.
No dump valve is required as the air is able to expand out of the end of the tube, care must be taken to keep tension on the bouy to keep it upright and avoid air spilling out.
The reflective strip is made using 3M scotchlite reflective tape which carries a SOLAS maritime visibility certificate.
A clear plastic tube is fitted to the side of the XDeep SMB to provide a place for small notes or a glow stick.
A big sling underneath makes attatching a spool or reel easy and also make filling the bag a breeze, a small loop of bungee keeps the SMB neat and tidy in storage.