It seems like you might be referring to a specific product related to "Benz" and "thin pencilling," possibly in art or drafting tools that could include a 4mm diameter or a 4-megapixel feature. However, your phrase isn't very clear.
If you're referring to a type of pencil, "Benz" could denote a brand or specific product line, and "thin pencilling" could suggest that you are talking about thin-tipped pencils or markers used for detailed work.
Could you please provide more context or clarify what exactly you're looking for? This way, I can offer more accurate information or assistance!