Diamond-cut 4-ball beauty facial roller, made of stainless steel for a luxurious feel. - Type: Facial roller - Material: Stainless steel - Number of balls: 4 - Design: Diamond cut Thank you for viewing. I purchased this item, boxed, on this site about two years ago. I have lost the card with the serial number, etc. There are no problems with using the roller itself, and it moves smoothly. Looking at the third photo, the large balls don't appear symmetrical, but it seems there are no issues with its use.