Peak UK have released their own version of the rescue tape.  This bright yellow 5m long tape is constructed from 20mm tubular tape.

Peak UK Rescue Tape
5m of rescue tape

If you are paddling whitewater I would strongly recommend having a length of rescue tape like this Peak UK version or the ones from Palm or Whetman Equipment.  

You could even make your own using climbing tape but you will need to tie loops into it.

These tapes work best with a large carabiner.  Peak UK do a non-locking carabiner for this exact purpose.

Rescue tapes are a versatile bit of gear that can be used for setting up belay points, towing, or short reach rescues.