You must be logged in and verified to contact the designer.
This elbow is part of a set of pipe fittings that are designed to connect to Evergreen #224 tubing. This tubing has an Outside Diameter (O.D.) of 0.125″/3,2mm and an Inside Diameter (I.D.) of 0.069″/1,8mm.
By gluing a length of tubing to the flange you end up with two flanged pipes bolted together