Base Flange, 1 1/4 in For Pipe Size, Structural Pipe Fitting - 54WK21|46-7 - Grainger
Guardrail Base Flange
48 Heavy Duty Rectangular Base Flange 1 1/2" – Mutual Hardware
Amazon.com: Structural Fitting, 1-1/2" Round Base Flange, 31F-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". : Industrial