Compact oxygen closed circuit rebreather


SEAL MK1 PRO is the most compact and lightweight oxygen closed circuit Underwater Breathing Apparatus (UBA), designed and manufactured by SIEL for shallow water and short and medium duration missions.


  • Closed circuit oxygen rebreather, chest mounted apparatus (or back mounted with optional dorsal kit).
  • Weight and dimensions highly reduced compared to other rebreather of the same class.
  • High level of reliability, strength and a simple maintenance by hand only without tools.
  • Very big breathing bag volume.
  • Innovative radial type soda lime filter designed for maximum sodalime performance and low work of breathing.
  • Excellent hydrodynamic fitness.
  • Automatic (demand valve) and manual (by-pass) oxygen injection control.


  • Max operational depth: more than 12 mt (40fsw)
  • Operative depth: Pure oxygen diving rules in your Country
  • Dive Time: 100 min
  • Storage Temperature: -30°C > 70°C (-22°F > 158°F)
  • Operative Temperature: -2°C> 40°C (28°F > 104°F)
  • Breathing bag capacity: variable volume, ~ 8.5 lt (0,3 ft3)
  • Radial filter capacity: 1.35 kg (2,98 lb) of soda lime
  • Oxygen cylinder capacity: 0.80 liter  @ 200 bar (total 160 liters)
  • Dimensions  mm (HxWxD): h420 x w350 x d120 mm (16.53x13.77x4.72 inch)
  • Dry weight: 6,7 kg (14.8 lb) w/out soda lime & oxygen / 8.4 kg (18.5 lb) ready to dive (+ 1,5Kg ballast)
  • Weight in seawater: neutral with 1 liter of oxygen in the bag

For more informations please contact us on

SIEL S.r.l.
Torino Plant: via Postiglione 24, 10024, Moncalieri (TO) - Italy
Spezia Plant: via Vincinella 14, 19037, S. Stefano di Magra (SP) - Italy
VAT registration number: 04201240019