Check the listing for details. Devardi Glass Graphite Marver~ DONUT BEAD ROLLER/SHAPER, Lampwork Bead Making. Condition: New. Listed at 36.95 USD. Domestic shipping fees are no additional charge. We combine shipping for international orders! International customers please request an invoice before paying if you purchase multiple items. Thank you. Made in the USA, exclusively by Devardi Glass. This great roller/marver makes donut shaped beads easily and fast, usually in one pass. Two sided, eight slots. Marver measures 3 x 2-3/4 x 1 inch. Slot sizes, from small to large: 1/4 inch width - 3/16 & 1/4 inch deep. 3/8 inch width - 1/4 & 3/8 inch deep. 7/16 inch width - 5/16 & 7/16 inch deep. 1/2 inch width - 3/8 & 1/2 inch deep. To figure bead size, multiply the depth by 2, and add the mandrel width. For example: The 3/16 inch deep slot, using an 1/16 inch mandrel, will produce a 7/16 inch bead. 14 day return policy. Thanks for looking.