Product Code: EHYG2, Model: 14x17 Green RE 400 Screens and Cassettes, Product Code: EHYCT, Model: 14x17 Green RE 100 Screens and Cassettes, Product Code: EHX5C, Model: 14x17 Blue RE 800 Screens and Cassettes, Batch number are a combination of 4 letters/numbers xxyy, where xx varies alphabetically form 6N and 6Z and from 7A to &N; and yy is a number from 01 through 31. Batch numbers are located both on the cassette shell and on the outer label.