From the Aurora Aperture YouTube Channel:
One Set of Filters for Every Lens
Aurora Aperture Adapter Mount Format Filter (AMF) filter is a revolutionary filter format that works for all DSLR lenses on popular mirrorless mount adapters. You will only need one set of filters for all your adapted lenses, no more multiple sets of filters or step-up rings, or complicated and bulky square filter systems.
The AMF drop-in filters work extremely well with ultra wide-angle lenses, especially those that have a protruding front element and are without front filter threads. Those types of lenses require a bulky filter adapter paired with very large filters. They are inconvenient to carry around and are unfriendly to your wallet. The AMF Filters is currently available through a kickstarter.com crowdfunding campaign.