Small
Looking for a replacement jet for your T-108S?  This is it.
Perhaps you want a smaller diameter flow screw than the one that came standard with your Tucker® aluminum pole.  
This orifice is much smaller allowing those who want to preserve water to do so.
Addtionally you can get better performace from this jet when using a low flow system like RO/DI vs. DI only.
 
 
Large
This is the standard Tucker® pencil jets screw that would have came with your aluminum pole.
Large diameter for max flow.