There is not a blanket statement that everyone uses. But they aren’t that different. There is a lot of variation on this theme below. This one is for information/data but easily modified for hardware. But be careful not to use it with non-controlled information/items. It shouldn’t be used on all things as a CYA. It also shouldn’t be used for export/delivery to a non-US person. That needs to be more specific.
EXPORT SENSITIVE: ITAR CONTROLLED
This document contains Technical Data whose export is restricted by the Arms Export Control Act (Title 22, U.S.C., Sec 2751, et seq.). Violations of these export laws are subject to severe criminal penalties. This data may not be resold, diverted, transferred, transshipped, made available to a foreign national within the United States, or otherwise disposed of in any other country outside of its intended destination, either in original form or after being incorporated through an intermediate process into other data without the prior written approval of the US Department of State.
This is just one of many things to that need to be done for compliance. Check out the DDTC website of the State Department. They are a good information source. There is a link to a pdf on this page that is a good start point.
https://www.pmddtc.state.gov/compliance/index.html