Check-Flex G4-F Duckbill Check Valve

Check-Flex Flanged Duckbill Valve for pipe or wall mounting

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Vulcanised and reinforced like a tyre for durability

Flexible and wide seal

Flange drilling to match any mating flange

Sizes to fit all pipes

Encapsulated metal with strong single piece design for marine diffuser applications

Nominal Pipe Size

Check-Flex G4-F0050
OD: 165mm
L: 160mm
H: 142mm

PN6: BCD Ø110mm 4x M12
PN10: BCD Ø125mm 4x M16
PN16: BCD Ø125mm 4x M16
Check-Flex G4-F0080
OD: 200mm
L: 232mm
H: 210mm

PN6: BCD Ø150mm 4x M16
PN10: BCD Ø160mm 4x M16
PN16: BCD Ø160mm 4x M16
Check-Flex G4-F0100
OD: 220mm
L: 270mm
H: 225mm

PN6: BCD Ø170mm 4x M16
PN10: BCD Ø180mm 8x M16
PN16: BCD Ø180mm 8x M16
Check-Flex G4-F0150
OD: 285mm
L: 340mm
H: 380mm

PN6: BCD Ø225mm 8x M16
PN10: BCD Ø240mm 8x M20
PN16: BCD Ø240mm 8x M20
Check-Flex G4-F0200
OD: 340mm
L: 360mm
H: 455mm

PN6: BCD Ø280mm 8x M16
PN10: BCD Ø295mm 12x M20
PN16: BCD Ø295mm 12x M20
Check-Flex G4-F0250
OD: 405mm
L: 450mm
H: 520mm

PN6: BCD Ø335 12x M16
PN10: BCD Ø350 12x M20
PN16: BCD Ø355 12x M24
Check-Flex G4-F0300
OD: 460mm
L: 605mm
H: 610mm

PN6: BCD Ø395mm 12x M20
PN10: BCD Ø400mm 12x M20
PN16: BCD Ø410mm 12x M24
Check-Flex G4-F0350
OD: 520mm
L: 640mm
H: 680mm

PN6: BCD Ø445mm 12x M20
PN10: BCD Ø460mm 16x M20
PN16: BCD Ø470mm 16x M24
Check-Flex G4-F0400
OD: 580mm
L: 705mm
H: 790mm

PN6: BCD Ø495mm 16x M20
PN10: BCD Ø515mm 16x M24
PN16: BCD Ø525mm 16x M27
Check-Flex G4-F0450
OD: 640mm
L: 760mm
H: 840mm

PN6: BCD Ø550mm 16x M20
PN10: BCD Ø565mm 20x M24
PN16: BCD Ø585mm 20x M27
Check-Flex G4-F0500
OD: 715mm
L: 785mm
H: 960mm

PN6: BCD Ø600mm 20x M20
PN10: BCD Ø620mm 20x M24
PN16: BCD Ø650mm 20x M30
Check-Flex G4-F0600
OD: 840mm
L: 970mm
H: 1100mm

PN6: BCD Ø705mm 20x M24
PN10: BCD Ø725mm 20x M27
PN16: BCD Ø770mm 20x M33
Check-Flex G4-F0700
OD: 840mm
L: 1100mm
H: 1300mm

PN6: BCD Ø810mm 24x M24
PN10: BCD Ø840mm 24x M27
PN16: BCD Ø840mm 24x M33
Check-Flex G4-F0800
OD: 1025mm
L: 1150mm
H: 1390mm

PN6: BCD Ø920mm 24x M27
PN10: BCD Ø950mm 24x M30
PN16: BCD Ø950mm 24x M36
Check-Flex G4-F0900
OD: 1125mm
L: 1330mm
H: 1690mm

PN6: BCD Ø1020mm 24x M27
PN10: BCD Ø1050mm 28x M30
PN16: BCD Ø1050mm 28x M36
Check-Flex G4-F1000
OD: 1255mm
L: 1340mm
H: 1770mm

PN6: BCD Ø1120mm 24x M27
PN10: BCD Ø1160mm 28x M33
PN16: BCD Ø1170mm 28x M39
Check-Flex G4-F1200
OD: 1485mm
L: 1540mm
H: 2070mm

PN6: BCD Ø1340mm 32x M30
PN10: BCD Ø1380mm 32x M36
PN16: BCD Ø1390mm 32x M45
Built to Order
Specify flange hole pattern
Table displaying model, style, pipe size range, and pipe connection options for various products.

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ModelStylePipe Size RangePipe Connection
-S-C-W-F / -Fi / -Fd-G
G5Inline Fabricated80–3000mm----
G5MInline Moulded100–150mm-
G5-RESIInline EN13564-180–200mm-
G4Duckbill Fabricated100–2400mm-----
G3Duckbill Fabricated100–2400mm-----
G3MDuckbill Moulded100–150mm-
G2Inline Duckbill Fabricated50–300mm-