Amazon.com: 2 Pack 12mm Flange Coupling Connector, Rigid Guide Steel Model Coupler Accessory, Shaft Axis Fittings for DIY RC Model Motors, High Hardness Coupling Connector-Silver. (2 pcs 12mm) : Industrial & Scientific
uxcell 5mm Inner Dia H15xD15 Rigid Flange Coupling Motor Guide Shaft Coupler Motor Connector for DIY Parts Black 4pcs: Amazon.com: Industrial & Scientific
Stainless Steel 316 Grade Floor or Wall Base Flange for 2 x 2" Post - - Amazon.com
Amazon.com: Structural Pipe Fitting, 1-1/2" Wall Flange - Triangle, 51B-8, Aluminum Magnesium, Please note. ID of fitting is 1.925, to take nominal 1-1/2" steel pipe which all have an OD of 1.9". :
Amazon.com : TSRETE Flange Compatible with S9/S10/S12 Parts Replaces, Hands Free Breast Pump Shield/Flange, Breast Pump Parts Replace(27mm) - 1 Pc : Baby