Kadam is a network established in 2012 that reports 37-40 billion monthly impressions across all its formats, with popunder (called clickunder on the platform) generating over a billion daily impressions on its own. Coverage spans 195 countries, and the network explicitly lists adult as a high-performing category. The minimum deposit sits at $10, which keeps the barrier low for testing new traffic sources, and multi-factor moderation vets publisher supply for quality.
The dashboard and documentation feel a generation behind modern DSPs. A usability trade-off for the price and volume access.