Wedge, Plate 4 x 4, LEGO® Part# 43719.  Alternate Part# 41822.

This part has multiple variants that are considered the same part.  All parts will have the same function but may vary in structure of the underside.

To learn more about the parts we offer, email us at info@atlbrick.com or call us at our storefront at 470-414-2208 and we'll be happy to help to answer any questions you may have.