Capillary depth gauges are very inexpensive with a simple piece of clear tubing, sealed at one end and open at the other. When you dive the water goes in the tube by the ambient pressure. At 10 m it is half the length of the tube, 20 m a third, etc based on Boyle’s Law. They are hard to read accurately at much deeper than 10 m.
Combining several capillary tubes in one depth gauge ,
which measure the depth in different ranges, will allow
obtaining a measuring scale close to linear and eliminate the
main disadvantage of a capillary depth gauge.
in the photo you can see that in the Mark 25 model, in the middle of the capillary length there is a mark of 6 meters. But the Boyle-Marriott law continues to work!
The depth gauge weighs only 19 grams with strap.
Diameter - 40 mm.
Hihg - 7 mm
Therefore, it is ideal for snorkeling, freediving and spearfishing.
The depth gauge will not be heavy even for a child’s hand.
Ideal for a back-up depth gauge - adds no weight or space, no batteries and operational at any depth.
- Beginner Divers: The most budget and useful device that will accompany you from the first days of learning and throughout your long career as a diver as a back-up and master reference depth gauge.
Complete with dive watch is absolutely sufficient kit for unsaturated dives within the permitted range for Open Water Divers.
You can choose your own dive computer later.
- Free diving, snorkeling and speerfeeshing: Thanks to its minimal dimensions, it makes the swimmer absolutely free and will always show the correct diving depth. Suitable even for children!