An expandable ad starts as a slim banner and grows over the page when someone hovers or taps it, then folds back. Wirtualne Media sells one that sits above the navigation bar of its website.
How it's sold
Only one publisher lists it so far, so you book through Wirtualne Media's own sales team.
What it costs
Most publishers quote it on request, and the usual basis is a flat fee per week or month, or per 1,000 impressions.
What you supply
You supply the collapsed banner, the expanded artwork and any HTML5 files the publisher asks for, usually with a close button.
Best for
It suits product launches where you want room for a bigger message without a permanent large unit.
Before you buy
Ask whether it expands on hover or on a click, since accidental expansion can be counted as engagement and lead to wasted spend.