Establish how the gasket mounts to the door. It should fall into one of four styles: screw on, snap-in, push-in, or panel gripper.
Compare your gasket to the Gasket Profiles page or your sample ring. Compare thickness, width and magnet width.
For flange-type gaskets specify dimensions from outside edge to outside edge, making sure to measure from the widest point of the gasket.
For dart-type gaskets specify dimensions between the tips of the snap-in darts.
Make Sure to Check these Items
Note the number of sides. Most walk-in gaskets have only 3 sides.
Some gaskets do not have a magnet on the hinge side. If this is the case for a 3 sided gasket, be sure to note if the door is hinged left or right. For a 4 sided gasket, note which length has no magnet.
Gaskets are guaranteed to 1/8″ of specified dimensions.
All gaskets are measured outside corner to outside corner unless specified dart to dart.