McEver Distributors

Latest News

By in Uncategorized 0

What are the numbers and letters on my CO² tank?

Our more curious home brew clientele may be wondering what the stamped writing is on their CO² tank. The answer is likely what you might have expected, most of the information is regulatory. Consumers will find the most relevant information is the original hydrostatic test date and the service pressure of the tank.

For the benefit of newer home brewers  (and dispensers) – A Hydrostatic test is a test that determines the integrity of a tank to hold pressure. A typical CO² tank is required to undergo hydrostatic certification every 5 years. We’ve included the full breakdown of the information on a CO² tank thanks to Catalina Cylinders.


The Department of Transportation (DOT) requires cylinders made in compliance to their specs and be marked on the crown with certain information.


Below is an example of the current crown marking stamped on any CO² tank.

DOT-3AL1800FXXXXXXX M4002 07C08 B20 U18 T25.2LB TC-3ALM124 T11.5KG CATALINA

Marking Description
DOT-3AL U.S. regulatory authority and specification, 3AL, (required mark).
1800 Service pressure, in pounds per square inch (psi), of the cylinder (required mark).
FXXXXXXX Serial number of the cylinder. 
M4002 M-number or Manufacturers Number 
07C08 Original hydrostatic test date of the cylinder, month followed by year, performed at the time of manufacturing.
B20 Cylinder identifier (product name).  “B” for beverage, and capacity “20” 
U18 Cylinder outlet thread designation as specified in CGA TB-16.
T25.2LB or TW25.0LBS Tare weight (in lbs.) of the empty cylinder package. 
TC-3ALM Canadian regulatory authority, 3ALM, to which the cylinder is manufactured in compliance.
124 Service pressure of the cylinder expressed in metric units, bars (required mark).
CATALINA Name of the manufacturer of the cylinder.
T11.5KG Metric tare weight (in kgs) of the empty cylinder package. 


Tanks are certified before being shipped, new and used CO² tanks can be purchased in our online shop.

Post navigation

Leave a Reply

Your email address will not be published. Required fields are marked *