Lotion Applicator Testing

I'm looking for a retractable lotion/sunblock applicator roll-on to be tested for functionality and usability. the roll on is not ball but cylinder. The product will be used by both adults and children.

Key Requirements:
- Test the product's functionality and usability
- Suitable for both adults and children

Ideal Skills and Experience:
- Experience in product testing
- Attention to detail
- Ability to provide comprehensive feedback

Your insights will help refine the product for end-users.