The Y8735 part number is a Lennox replacement part number but the part is actually made by Sanhua a reputable Chinese HVAC parts supplier for many refrigeration manufacturers. The txv appears to be well made and it fit perfectly in a Lennox air handler. It is slightly taller than the original because this TXV has an adjustment nut on the bottom. It came with basic installation instructions that included the critical torque values for all the connections. It is working well and I recommend it.