What is the advantage of PTW then other AEG? PTW can swap the upper to create different settings for mission and impression.

Here we represent you the HAO's M27 RWK kit.
 
RWK's full name is M27 "Reconnaissance Weapons Kit" (RWK). It's a variant of the USMC Marine M27.  
Features with an 11.0” barrel / 416A5 upper/ RWK version 416A5 style handguard ( front iron sight removed, filled with full picatinny rail) / 416A5 gas block.
 
This kit transfer a standard M27 into a lighter, shorter partner for marine corps

**COMPATIBLE WITH ORIGINAL SYSTEMA PTW M4 LOWER RECEIVER**
 
Anodizing/surface treatment disclaimer :
Anodizing is a serious chemical process that is fairly unstable. The shade of color can vary batch by batch. We do our best to make the color as correct as possible but we can NOT generate if the shade meets your imagination. Also to be noted that every monitor has its color differences. The color of the object and the color on your computer/ mobile device may be different. 
 
Made in Taiwan
BB type: 6mm 0.2g BBs
Power source: 11.1V PTW, AEG / 9KG green gas GBBR
Power: 90 m/s = 0.81J with 0.2g BBs
J / cm2:  2.835 J/cm2
Design and manufacture for Airsoft use. No live ammunition using function.