Richell Stainless Steel Mug Usable from 8 months Cup Mug Parts Designed so that the drink comes out a little at a time, so you can drink without choking. With Richell mug gasket There are 2 pieces, but I used 1. There is 1 piece remaining. Unused. - Brand: Richell - Model: Gasket P-1 - Compatible Products: B1435, B1521A, B1521B, B1404 Thank you for viewing.