The oxygen rebreather (A.R.O)  has been constructed with a waterproof bag that only cost a few Euro's, a piece of hydraulic hose (canister with telescopic function to vary the volume between 900 and 1700 grams of Sofnolime. Pressure on the sofnolime is added by the use of a elastic band that is mounted. The loop is constructed of pvc fittings and a corrugated hose(tecnoprene, milan).

I use a mouthpiece made of a 3-way valve normally in use for swimming pools. The valves are build in a separate pvc valve housing that are mounted on the mouthpiece.

The O2 cylinder is a surplus of my diving equipment, the rest is from a trekking backpack.

The autonomy is about 4 hours (with 1700 g of soda lime), but I tried it only for 2.30 hours !

 To make the ARO neutral I have to add 2.5 kg of weight. The oxygen bottle is supplied with a lever to manually add oxygen in the loop. The oxygen line is fitted with a large quick connector. To prevent the counterlung to 'stick' I add a couple of hair curlers in the counterlung.

 Simone Puzzolo, Italy.