Ok, on the ATF form 5320.20 there is no mention of suppressors in the instructions on the back. It list DD, MG, SBR, SBS, but no suppressors. I tried calling the ATF, and all I got was an answering machine and I left a message with my cell number. No reply. Can someone tell me if I need to use the form 5320.20 to travel out of state with my suppressor's? Or, is there another form? Edit to Add: Application to Transport Interstate or to Temporarily Export Certain National Firearms Act (NFA) Firearms Instructions a. A written request and prior authorization from ATF to transport interstate or in foreign commerce any destructive device, machinegun, short-barreled rifle, or short-barreled shotgun is required under the provisions of Section 922 (a)(4), Title 18, U.S.C., and Section 478.28, Title 27, CFR, a letter of request, in duplicate, containing all information required on this form, may be submitted in lieu of the form. b. The registered owner of NFA firearm(s) shall complete two copies of ATF Form 5320.20 and forward the forms to the Director, Bureau of Alcohol, Tobacco, Firearms and Explosives, 244 Needy Road, Martinsburg, WV 25405 (Attention: NFA Branch). c. All signatures on both copies of the form shall be in ink. A facsimile signature is not acceptable. All other entries on the form shall be printed in ink or typewritten. d. The original of ATF Form 5320.20 will be returned to the registered owner. Approval authorizes the registered owner to transport the designatedd firearm(s) only during the time period specified in item 3. THE AUTHORIZATION DOES NOT CARRY OR IMPORT RELIEF FROM ANY STATUTORY OR REGULATORY PROVISIONS RELATING TO FIREARMS OTHER THAN 27 CFR 478.28. e. In the event item 2 is checked “yes” and the firearm(s) is not returned to the original location by the date specified, the registered owner shall submit a new application on ATF Form 5320.20 to receive approval to return the firearm(s). f. If a contract or common carrier is used to transport the firearm(s) a copy of ATF Form 5320.20 shall be furnished to the carrier and shall be in the possession of the carrier for the duration of the transportation. This will meet the requirements of sections 922(e) and (f) of the Gun Control Act of 1968.