I finally received my FOTGA Automatic AF Macro Extension Tube DG FT1 10mm+16mm For Micro M4/3 from the eBay seller: They are mainly plastic, very light weight, with a metal face and camera flange. The lens side bayonet tangs are plastic, sitting under the metal facing. To be quite honest, construction wise, they feel and look no worse than the MMF-3 adapter and, with careful use, I'd say they should last reasonably well. Of course, these aren't weathersealed like the 4/3 extension tube, so all weather use would need to be tempered. Surprisingly, you can use these singly or together, and they also work fine (AF etc) when I attach my 4/3 tele-extender. You could never do this with the 4/3 cameras, only one extension tube or extender at a time. The tubes don't come with end caps, so this is something you need to consider if you don't have spares. I haven't included any photos, as I don't think that's relevant. All that really matters is their construction and operation on-camera and, to that end, I think they are quite reasonable for a $49 purchase.