Stainless Bros SS304 Saddle Type O2 Sensor Bung is a saddle style bung made from cast 304 stainless steel. The bracket piece has a rounded edge which allows for easy fit up and welding to your exhaust tube. The bracket design provides reinforcement to maintain the structural integrity of the exhaust tube by spreading the load, once the O2 sensor bung is in place. Specifications: Application: Saddle type Weld-on Bung Material: 304 Stainless Steel Thread: M18 x 1.5mm Quantity: Single Bung Part #: 604-00100-6000