The product is a set of 50 white W2 2-Up tax form envelopes designed for use with Quickbooks Desktop and other applications. These envelopes are made of paper and have dimensions of 9.25 x 5.63 x 0.04 inches. They are lightweight, weighing 12.3 ounces, and are suitable for mailing tax documents and letters. The item model number and manufacturer part number are both 6666125.