Washer/O Ring Size

[Breck09]

Getting back into brewing after a long layoff and putting my keezer back together. I ordered some new parts to replace old/crusty parts that I had thrown away. I ordered a new nut to screw onto the shank along with a barb for the beer line but thinking I need a washer/o ring as well. Anyone know what size I would need. Hoping to get it from Lowe’s or Home Depot.

 

[day_trippr]

Take it to HD or Lowes or wherever, should be able to find something close to a beer washer.
Any flat rubber o-ring that's close to and does not exceed the diameter of the wide/flat section of the barb will work.

Cheers!