This battery vent adapter was made to fit our #4000600 Battery Water Level Indicator on a Varta RL 840 battery (made by Enersys). But this adapter will fit any battery that has a vent hole with M27-3 threads. In addition, this adapter lets you fit all 1/4-turn bayonet-style vent caps on your battery. The part drawing can be viewed online to see the dimensions.
Also, we make more adapters that can be viewed by choosing one of these links.
#4D-8D-PIA Battery Vent Adapter
#4D-8D-SIA Battery Vent Adapter
#1050VCA Battery Vent Adapter
#M22X1.5 Battery Vent Adapter