I am planning to assemble a flashlight to test how the custom emitter works. Then I might sell it off later on since it may become redundant. The problem is I’m currently only have leaded solder, and that might be a problem if those flashlight were to be shipped to EU from Non-EU countries.

If I were to ship a modded flashlight to EU. Do I need to use a lead free solder for assembling? Does the RoHS marking required?

Is this something that is being sent by a private individual or by a commercial enterprise?

“Which companies are affected by the RoHS Directive?
Any business that sells or distributes applicable EEE products, sub-assemblies, components, or cables directly to EU countries, or sells to resellers, distributors or integrators that in turn sell products to EU countries, is impacted if they utilize any of the restricted materials. Since RoHS-like regulations have spread to a number of other countries, this just doen’t apply to EU countries anymore.”

copied from https://www.rohsguide.com/rohs-faq.htm

If this is what you mean;

I would send as an individual. This is most likely something that will happen only few and far between.

I just don’t think it makes sense for me to splurge on a spool of lead free solder (and a new tip to prevent cross-contamination) for a few flashlights.