Tecline - R4 TEC WW First Stage — EN250A

A lightweight, compact, membrane-controlled first stage with a wet chamber, rated EN250A for water above 10 °C. At 590 g it is the one that goes in the travel bag.

The design choice worth understanding: it has no environmental diaphragm. That is deliberate. An environmental diaphragm can overbalance at depth and interrupt gas flow — removing it removes that failure mode, at the cost of cold-water protection. Which is exactly why it is rated above 10 °C and not below.

Tecline rate it perfect for rebreathers and very good on stages and twinsets. They rate it not recommended for sidemount, and that is their word, not a hedge of mine — if sidemount is what you dive, look at the R2 TEC instead.

Body is chrome-coated maritime bronze with a balanced main valve, 2 HP and 4 LP ports, and a 300 bar working pressure.

Specifications

• Type: membrane, balanced main valve
• Chamber: wet, no environmental diaphragm
• Certification: EN250A, above 10 °C
• Ports: 2 HP, 4 LP
• Working pressure: 300 bar
• Material: chrome-coated maritime bronze
• Weight: 590 g
• Tecline rating: rebreather perfect, stage very good, twinset very good, single good, sidemount not recommended
• Tecline code: T01410-4