Check the listing for details. Reznor Back Flow Sensor PN 121275. Condition: New. Listed at 36.00 USD. Quantity: (1) Back Flow Sensor # 121275 Item Specifics: Reznor Waste Oil Heater Replacement Part, Back Flow Sensor Mounts on Spring Loaded Observation Door This part is utilized on all Reznor Waste Oil Heaters. Shipping & Handling: FREE Shipping and orders placed before 3pm EST ship same day as ordered (when in stock).____________________________________________________________________________________________________________________________________________________ Factory Authorized Reznor Dealer in US. Daily shipping. Fresh stock. Order with confidence from us and get the right (OEM) part, at the right price! Heating Alternatives Inc has been an authorized Reznor Dealer since 1987. We sell OEM parts and ship waste oil heater parts everyday from our large warehouse. Our knowledgeable staff is always here to help answer any of your questions! ***Please visit our other listings for BRAND NEW Waste Oil Furnaces as well as PRE-OWNED/RECONDITIONED Units*** __________________________________________________________________________________________________________________________________ Please visit our Ebay store to see all of the waste oil heater parts we have available! Listing and template services provided by inkFrog