This just showed-up in my in-box (thanks, Elbereth!) and I haven’t seen it before. It’s the Sky Climber from Whisker Studio. It’s made of solid birch plywood finished with non-toxic water-based stain and clear lacquer. The shelves and the vertical scratchers (located above the first and second shelves) are covered with 100% natural woven sisal attached with non-toxic adhesive. The whole thing measures 72″ tall by 23″ wide by 18″ deep. It ships flat and you have to put it together, which they say will only take 30 minutes, but I guess that depends on how much IKEA assembly experience you have.