Placebos and blinded clinical trial kits fall under subheading 300693. FDA requires an Investigational New Drug (IND) application or equivalent authorization for investigational articles entering the US, and importers typically coordinate with the trial sponsor's regulatory team to ensure proper entry documentation.

Pre-assembled first-aid boxes and kits are specifically provided for in subheading 300650 of this heading, even when they contain a mix of bandages and medicament items. The kit's composite nature is resolved by the specific Note 4 provision rather than by classifying each component separately, provided the kit is put up for retail sale in that form.