Airsoft GI have sent over details of their custom G17:
RA Custom G17
Specification:
Original Frame for MARUI G-17/18C (EU. Black)
series No. Tag for MARUI /KJ GLOCK Series (Early Type)
New Age Steel Trigger set for WE Glock Semi series GBB
RA New CNC Steel Slide & CNC steel Outer Barrel
RA Desert storm CNC Steel Slide for WE G17 (BK)
RA Desert storm CNC Steel Slide for WE G17 (BK)
Specification:
FOR WE G17
Patented two-piece extractor
Outer barrel with corresponding serial number of the slide