Airtronics Dual Conversion RX xtal. Note, almost all Airtronics RX's in use today are FM and Dual Conversion. These take this yellow cap crystal. However, this same crystal also is correct for Airtronics AM dual conversion. For Airtronics crystals are only dual conversion or single conversion. There is no FM or AM crystal in this brand. Picture shows 2 crystals in two views as example only.
If you order one that is "No Longer Available", we will look in the exchange crystals and see if we have a used one to save your project.