A solo ad is a classic email advertisement that you purchase from someone else's email list. Then the owner of the email list will send out an email on behalf of you or the business you are representing to part or everyone on their email list.
Udimi offers access to many high-quality email lists of all niches. Their platform features a set of filters that you can use to find the right email list owners. That way, the user can have a highly targeted email campaign with plenty of high-quality leads that will eventually convert into sales.