Upgrade Kit, Glass Window, ABI 3900/Biolytic 3900, and Northwest, This changes the Window from homalite to Glass. This works with the original Biochem Valves or Burkert 127 valve.
This new window assembly is not setup to use the Activator Nozzle Wash Tower. 
It is expected that you will use your existing screws and nuts from the old window to mount this window assembly. However if you need new screws and nuts they are Part Number: Part Number: 283-102494-6 
This kit comes with a set of nozzle tubes. These are included because it is our experience that the existing nozzle tubes will be too short. The kit requires nozzle tubes that are 6.5 inch long. If you prefer to use your own nozzle tubes or to make your own nozzle tubes you can save some money and order Part Number 621-107715 which is the kit without nozzle tubes.
We will also offer a kit that includes the window kit and the parts to change the valves on any of these instruments from the original Biochem or Burkert to the new smaller Burkert valves. These new valves eliminate the long nozzle tube.