- Diam: 17.7 mm (inside dia)
- Colour : White
- Material : Polypropylene
- Cross-sectional area of opening : 1.53 cm²
| Type | Air flow rate | Pressure drop | Sound level |
| OPG 18 | 4 m³/h | 3 mm w.p. | 28 dB(A) |
| 7 m³/h | 6 mm w.p. | 32 dB(A) | |
| 10 m³/h | 10 mm w.p. | 36 dB(A) |
Capacity Chart for Exhaust Air Valve – OPF 80
Capacity Chart for Exhaust Air Valve – OPF 100
Capacity Chart for Exhaust Air Valve – OPF 125 & 125K
Capacity Chart for Exhaust Air Valve – OPF 150 & OPF 160
Capacity Chart for Exhaust Air Valve – OPK 100 & 100K
Capacity Chart for Exhaust Air Valve – OPK 160 & 160K
Capacity Chart for Exhaust Air Valve – OPK 200df
Capacity Chart for Supply Air Valve – OPT63
Capacity Chart for Supply Air Valve – OPT100E
Capacity Chart for Supply Air Valve – OPT125
Capacity Chart for Supply Air Valve – OPT150 & OPT160
Capacity Chart for Supply Air Valve – OPT200
Capacity Chart for Supply Air Valve – OPTS 100E
Capacity Chart for Supply Air Valve – OPTR 100
Capacity Table – OPG 41
