There are a number of Construction Battalions. Not everyone here knows what CB's means as far as construction battalions there are a number of active ones. You'r profile says you are 52. I suspect there have been many Battalions commissioned and deactivated since your father was active duty. Kinda why I asked. Listed below are just the current active ones. There were over 140 commissioned Battalions during WWII.
So if you want help locating something for an inlay a little more info would help. I'd almost suggest having something laser etched. If it's a really old Battalion you may not be able to find something to use as an inlay if its a decommissioned battalion.
If you want to emulate what is on the zippo post a picture of it. There is no way to know what insignia is on it without seeing it. Every Battalion has it's own.
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