We manufacture battery vent cap adapters to convert most batteries to accept any bayonet-style vent cap. Further, our invention solves the need for adapting any standard bayonet battery cap to fit virtually any deep cycle battery. This includes 4D, 8D, marine, solar, 12-volt, European style, and other batteries. There are many reasons why you may need an adapter to replace the original battery vent cap. Some of them are listed below. 1) The original vent cap is broken or lost, and you need a replacement. 2) You want to replace the original cap with a red, yellow, blue, orange, black, or white vent cap. 3) The original vent cap does not contain a flame arrestor and therefore you want to replace it with one that does. 4) The original vent cap is too short which can cause the top of the battery to become wet with electrolyte. In this regard, a taller vent cap helps to keep batteries dry. 5) The original vent cap allows the electrolyte to evaporate too quickly. Not only that but replacing it with a Water Miser cap reduces evaporation which means you do not need to add water as often. 6) You want to replace the original vent cap with a water level indicator so you can check the electrolyte level without removing the vent cap.
We make multiple adapters
Whether the original vent caps on your battery are the screw-in type (threaded) or the push-in style, we make an adapter that adapts any bayonet-style vent cap to most batteries. To order, select the picture of the adapter you need to enter our online store. We make battery vent cap adapters to fit most batteries. Further, this includes threaded and push-in style 4D and 8D batteries with a 3/4″ round vent hole. Also, our 1050VCA adapter fits push-in style European batteries and some models of Douglas batteries. In like manner, we make screw-in adapters to fit threaded-type batteries including those with metric threads. In addition, the items listed on this page are adapters only. The battery vent cap is not included and must be purchased separately. For more information on how to select the best vent cap model for your battery, please visit our FAQ page.
Battery Vent Adapter, Model #4D-8D-SIA
- Fits 4D or 8D batteries with screw-in caps
- Converts 7/8″-9 UNC threaded batteries to accept 1/4-turn bayonet caps
- Screw-in style with rubber seal (included)
- Made in the USA in our Ohio factory
You may order this threaded adapter in our online store.
Battery Vent Adapter, Model #4D-8D-PIA
- Fits 4D or 8D batteries with push-in caps
- Convert 3/4″ diameter push-in style batteries to accept 1/4-turn bayonet caps
- Push-in style (no seal is required)
- Fits all batteries with 3/4″ diameter vent holes
- Made in the USA in our Ohio factory
Dress up your car’s engine compartment! With that in mind, this battery vent adapter lets you replace the original plate-style vents that cover all 3 holes with our yellow, red, blue, orange, black, or white battery caps. Moreover, this vent adapter fits 3/4-inch diameter vent holes. Please measure your battery before ordering. You may order this push-in adapter in the online store.
Battery Vent Adapter, Model #M22X1.5
- Converts M22x1.5 threaded batteries to accept 1/4-turn bayonet caps
- Screw-in style with rubber O-ring seal (included)
- Made in the USA in our Ohio factory
You may order this M22x1.5 adapter in the online store.
Battery Vent Cap Adapter, Model #M27X3-SIA
- Converts M27x3 threaded hole to accept 1/4-turn bayonet caps
- Screw-in style with rubber seal (included)
- Made in the USA in our Ohio factory
You may order the M27x3 adapter in the online store.
Battery Vent Cap Adapter, Model #1050VCA
- Fits European push-in style batteries
- Fits some batteries manufactured by Douglas Battery Co.
- Converts 1-3/8″ diameter hole to accept 1/4-turn bayonet caps
- Push-in style with rubber O-ring seal (included)
- Made in the USA in our Ohio factory
You may order the 1050VCA adapter in the online store.