USA Industrials - Aluminum Pipe Fittings; Material Grade: Class 150 - 28850972 - MSC Industrial Supply
Amazon.com: Structural Pipe Fitting, DIY Outdoor, Use Imagination -1-1/2"Tee-E Short, 3T-8, Aluminum Magnesium, Note: ID of fitting is 1.925, to take nominal 1-1/2" steel pipe which all have an OD of 1.9". :
Kee Lite Type L62 Aluminum Pipe Fittings - Standard Railing Flanges | Hoover Fence Co.
USA Industrials - Aluminum Pipe Fittings; Material Grade: Class 150 - 28850808 - MSC Industrial Supply
Amazon.com: Structural Pipe Fitting, 1-1/4" Cross - E Short, 21X-7, Aluminum Magnesium, Please note. ID of fitting is 1.68, to take nominal 1-1/4" steel pipe which all have an OD of 1.66". :