888-354-0291 740-622-3307
111 North 14th St • PO Box 218 • Coshocton, OH 43812

Filler Breather – Bayonet Style

These filler breathers have a bayonet fitting and are used in a wide variety of hydraulic tank reservoir systems. Filler breathers are essential when air exchange is needed and there is a risk of air-borne contaminants and particles. With a handy steel grip cap, our bayonet-style filler breathers come with a standard wording on dipstick “Full” & “Add”, but we can custom print wording as well. Contact us to discuss your requirements.


  • Pressurized breathers (OBB-P style) provide clean air flow into reservoirs where there is an exchange of air during changes in tank fluid levels
  • Available with grip cap as a standard product
  • Pressurized breathers provide positive suction head at the pump inlet
  • Easy to  install


  • Steel cap with multiple cap finishes
  • Air intake valve opens at 0.435 PSI/3 KPԚ
  • Temperature range: -22°F to 240°F
  • Relief valve setting at 5 psi/.34 bar
  • Default wording on dipstick “Full” & “Add” – Custom wording upon request



Standard Options – All Styles

  • Multiple cap finishes (all styles) – zinc plated standard
  • 3”, 6”, 8” stainless and 4” nylon basket
  • Oblong, round or no mounting holes
  • Multiple flange options with locking tabs
  • Multiple gaskets
  • Multiple link chain
  • Rivet bayonet

Cap FinishCode
Black E-CoatB
Chrome PlatedC
Zinc PlatedZ
Filter for OBB & OBB-P OnlyCode
3 micron OBB Only3
10 micron10
40 micron40
3" Stainless Steel 3S
6" Stainless Steel 6S
8" Stainless Steel 8S
4" Nylon4N
Oblong Mounting HolesFO
Round Mounting HolesFR
No Mounting HolesFN
Oblong Mounting Holes, Locking TabFL
Base Style for OBB & OBB-P OnlyCode
Bayonet BlackB
Bayonet Zinc (Clear)Z
Bayonet with Locking Tab (Zinc)LTZ
Bayonet with Locking Tab (Black)LTB
Base Style OBN Only
No Hole Bayonet (Zinc)NH
No Hole Bayonet with Locking Tab (Zinc)NHLT
Available OptionsCode
14 Link Chain with Small RingC1
10" Chain with Small RingC2
Rivet BayonetRB
Neoprene CorkNC
Dipstick (Contact Factory)D
Standard on All Styles
6 Pack Screw Kit
Buna Gaskets
All dimensions are in inches and for reference only.

How to Order: OBB-P (Pressurized) series - Chrome plated, 40-micron, 6" basket, Round holes, zinc base = OBB-P-C-40-6S-FR-Z

StyleCap FinishFilterBasketFlangeBase ColorOption

How to Order: OBB (Vented) series - Vented, Chrome plated, 40-micron, 6" basket, round holes, zinc base = OBB-C-40-6S-FR-Z

StyleCap FinishFilterBasketFlangeBase ColorOption

How to Order: OBN (Non-Vented) series – Chrome plated, 6” basket, Round holes, No hole bayonet, zinc plated = OBN-C-6S-FR-NH

StyleCap FinishBasketFlangeBase ColorOption