If there is no Manufacturer on the firearm, enter “None Marked” in the A&D Record. Do not leave it blank and do not write N/A.
Per ATF Regulation, information entered into your A&D record and subsequent 4473s should only be what is stamped or marked on the firearm.
The information used in the A&D record should match what is listed on the Form 4473 when the gun is sold.