Single Stage Vacuum Inlet Trap

  • Positive Flow
  • No “blow-by”
  • Variety of elements
  • Positive trapping
  • Easy changing and cleaning

The flow of the effluent gas is directed through the inlet port to the filter elements. Unlike other traps, the filter elements of the POSI-TRAP® are sealed at both the inlet and the exhaust ends, eliminating blow-by and maintaining a positive flow through the elements. This means all contaminants must pass through the filter medium.

Choose from stainless steel gauze, copper gauze, molecular sieve, Soda Lime, activated charcoal, and PolyPro (2, 5, and 20 microns). One (4″ Posi-Trap) or four (8″ Posi-Trap) filter elements are required per trap.

Other filter media is available. We can also customize filters for your specific application. For more information on filter media and applications, click here.

Construction Stainless steel
Seals Buna N O-rings
Dimensions Refer to Installation Drawings
MV Products offers several interchangeable inserts:
Type Description
Copper gauze Large surface area traps condensable particles and oil vapors
Stainless steel gauze Same as copper gauze, but with added corrosion protection
Molecular sieve Reduces mechanical pump backstreaming and traps water vapor
Soda Lime Minimizes migration of corrosive chemicals and neutralizes acidic vapors
Activated charcoal Removes organic vapors
PolyPro 2μm Traps high volumes of solids and particulates as small as 2 microns; available in 3 sizes
PolyPro 5μm Same as above
PolyPro 20μm Same as above


Click following links to see drawings:
4″ Posi-Trap Models
8″ Posi-Trap Models


Description Part Number 4″ Size Part Number 8″ Size
Straight-Through POSI-TRAP:
With hose terminations 330000 340000
NW 25 flanges 330025
NW 40 flanges 330040 340040
NW 50 flanges 340050
Right Angle POSI-TRAP
With hose terminations 335000 345000
NW 25 flanges 335025
NW 40 flanges 335040 345040
NW 50 flanges 345050
 Filter Elements
(Quantity discounts for ten or more) Refer to chart below


Description Part Number
Copper gauze 300905
Stainless steel gauze 300915
Molecular sieve 300925
Soda Lime 300935
Activated charcoal 300945
PolyPro 2m 400925
PolyPro 5m 400935
PolyPro 20m 400945

Contact Us

5 + 12 =

Posi-Trap Single Stage Vacuum Inlet Trap