SELKIRK CORP 244230 4-Inch  90DEG Elbow Manufactured in china Easy to use Highly durable 4" inch, 4VP-90 Degree, Elbow, Type L Pellet Vent 3" inch clearance to combustibles Inner wall is constructed from stainless steel and the outer wall is paintable galvanized Rolled-over male end eliminates sharp edges Rated for flu temperatures up to 570 degrees F