UPDATE: “Coolest 2240 upgrade” Terrible build quality

Word of warning, I bought one of these and it just arrived. The Ebay description labels this as "fused deposition" and "fused polymer". Fool me once, as I read it quickly and thought, "oh hey it's polymer...cool." Not so much. It looks like a high school kid 3D printed it. The finish is rough and it feels like most cheap 3D printed things - like it's about to break. I owned a Bluefork a long time ago and sold it regrettably. This is nothing like the quality of the BF Designs. My opinion would be to avoid this part.

Fused deposition is a fancy word for 3d printing lol. And polymer is the material used, hence the label “fused polymer”, “fused deposition”. 
As for the looks it’s a from a guy on eBay who probably has a sub $1000 3d printer. If it were from a company with high end 3d printers I would be disappointed. But for $40 I’m not fretting about the usual 3d printed flaws like the lines from layering. 
That being said, if blue fork was still making them I would’ve bought one. I’ll take metal over plastic anyday
 
After shooting the 2240 with the new AR grip frame I can say it makes the trigger worse than the stock trigger. Completely takes away the 1st stage and makes the 2nd stage almost non existent. Feels like the gun will go off if I fart loud enough. While I like the ability to use an AR grip, the lack of trigger adjustability will make this part a dust collector.