It's looking like original part but its longer and angle for blowing air is exactly where is should be,now air blow just under the tip off the nozzle. Original duct nozzle was to short and air was blowing to much up on the nozzle.
Easy to assembly just re-screw on the same spot like on original air duct.
Keep In mind that CR10S and other CR10 models like S4 S5 , Cr10 mini and even newest Cr10 already have new molded fixed version of duct nozzle so this might not fit correctly. Look on your air duct nozzle is it 3D printed or is it made from molded plastic. If is made from molded plastic you probably dont need this upgrade.
You can also check the angle of blowing air.
Home your Cr10 and lift Z axis to aproximity 100mm then set coiling fan to 255(100%) and place your finger under the tip of the nozzle.
If most of air blowing under the tip of the nozzle then you are good.
If most of air blowing on the nozzle and up one the heated block then its not good.
I hope I helped :)
PLA works just fine.
Be gentle when you screwing down new duct nozzle.
It might need little bit of sanding on corner(screw place) to fit right.