I've bought and sold a handful of mid-century Zanesville ribbed planters and vases over the years of various sizes, and every time I find one think how good they are. I've never seen one in matte gray (charcoal, really) like this though, and think it's extra good. A perfect smallish planter.
5 1/2" in diameter x 4 5/16" t and in great vintage condition, no chips, cracks or other issues.