Here Pony pony pony
Today we officially release the classic PONY M4A1 PTW receiver . Both Gen I & II are in stock now !
You can see very clear the difference between two M4A1 in different ear with following pic.
The profile on the right side of upper receiver.
The rail number is milled on Gen II. Laser engraved on Gen I
The rib of back of the receiver is the biggest difference.