An inclosure in Connoisseur has a greater impact than a flyer in a mailbox. Also, it usually costs less with Connoisseur.
The advantage of an inclosure is that you set the level of the number of pages, the choice of graphic quality and the scope yourself. An inclosure that goes into the Connoisseur is observed by virtually 100% of the recipients to compare with the often inferior outcome of sending the inclosure directly via the Post Office to a household.
Choose an enclosure when you need more space or want to go with an offer.