First Pattern:

The first pattern was made of twill cotton poplin fabric, dyed Olive Green Army shade 107.  The jacket had four bellows pockets two slanted chest ones and two straight   lower ones, had an  inner gas flap at the front closure, shoulder loops, side tabs and exposed buttons.

The trousers had two front pockets, two hip pockets and two bellows cargo  leg pockets with drain holes and  leg ties, inside the left one was a small survival kit . The trousers were bloused over the boots by a tunneled draw string. The trouser had a five buttons fly with an inner flap and  a single button adjustable tabs on the waist.  All the pocket buttons were exposed! 

It is interesting to note that the 1st pattern jacket is worn with out US ARMY tape, Para qualification badge and SF shoulder patch, note the white T shirt which will be soon dye green  as per Military regulation (11/1965).

Photograph taken at DaNang in 1965,  courtesy of  SSG D Klehn, A-113 Sr Commo

This is the first pattern  Jungle jacket  and is from Sergeant First Class R Cameron A-113/A-103 and is one that he wore early on in his tour. The soldiers were issued two sets and the idea was to rotate them so that both sets aged evenly, but most "old hands" put one aside for inspections etc and wore the other one to hell. The one shown here is one of his day to day jackets. "Yes, I had more than two sets as I ran the supply shack." (Quartermaster Sgt). You will notice that there is no CIB or Wings! "Some of the guys had pin-on metal insignia", but he did not bother with these on his day to day jackets, his inspection shirt is badge to hell with Second Award CIB, Master Blaster (Master jump wings) and Vietnamese Jump wings and LLDB pocket patch.
"One thing you always tried to put up was your combat patch to kind of let know you had been around the block so to speak. In the early days, if you got a combat patch up you were more than likely a Korean Vet. A lot of the old Nancoms were, at that time, thought some SF guys had pulled some early TDs in Vietnam."
Words or sentence in "italic " are as written by R Cameron
Courtesy of R Cameron and Kevin Lyles

(my collection)

Second Pattern:

The second pattern was made of twill cotton poplin fabric, dyed Olive Green Army shade 107. The jacket lost the  inner gas flap at the front closure and the exposed buttons were now concealed under a flap to prevent snagging but the jacket retained the shoulder loops, side tabs .

The trousers   was identical to the first patterned but with concealed buttons.

Third and Final Pattern:

The third pattern was made of twill cotton poplin  at first then rip-stop cotton poplin fabric, dyed Olive Green Army shade 107.
By that time the shoulder loops and side tabs on the jacket were gone as well.

 The trousers had lost its leg ties, the five buttons fly was replaced by a zip with no inner flap and the single button adjustable tabs on the waist was replaced by a slide tab.