This is the unembossed 731 in dark orange-red amber that I won on eBay a couple of weeks ago. Without a light box, I have trouble getting good photos of really dark pieces. As you can see, the inside of the skirt has a shallow crackled surface. I've been told this has been seen before on 731's. The seller said they thought it was glue since these were glued on type insulators. Not true. The surface is crackled, but it is confined completely to the inside of the skirt and it's less than 1/32" deep. Even the pinhole is smooth. The rest of the insulator---including the base---is nearly perfect except for a few pencil ticks. Another seller offered an amber 731 'glue on' insulator with no threads and that auction just ended. Problem is, they used the identical photo from the auction I won. I was able to match it exactly by the position of the ticks on my piece and the photo. I wrote to both sellers and neither responded. The second seller was "dfandmz" and as Paul Greaves has shown, that seller tried to sell a brown mud piece as an amber threadless in mid Feb. I'd watch out for dfandmz auctions.