Suunto makes the most accurate and dependable dive computers on the planet, and William has used their gauges in all his training and record attempts since 2007. He currently uses a Suunto D6i, and depends on its accuracy and depth alarms in order to know exactly where he is during the descent - it has never let him down. It is also an invaluable tool to be able to log training and analyze dive profiles.

Orca is the manufacturer of the world's fastest wetsuits for triathlon, and have developed the Free and Breathe specifically for freediving. William uses the Orca Free in training and all record attempts. It's hydrodynamic qualities, combined with unmatched flexibility and minimal neoprene volume (to limit buoyancy change during a dive) make it the highest performance freediving wetsuit on the market. Orca also manufacture compression garments for recovery, and fashionable seamerino garments.

Clearwave Designs, LLC is the best web programming/graphics service available on the web.

Glorope is the best rope for freediving on the planet: zero-stretch, glow in the dark and stronger than steel wire.

One of the most accomplished freediving photographers in the world, Igor Liberti has supplied many of the underwater images used on this site.

The Worldwide Federation for breath-hold diving, responsible for officiating competitions and homologating world records.

The homeliest hotel close to Dean's Blue Hole, and site of many of Vertical Blue's closing night dinners and celebrations!