What with M1 liners being so confusing i thought i would put this easy guide up.
It covers ONLY US MADE INFANTRY LINERS-no Nato or Airborne liners.Also im not going to confuse people anymore with the correct designation of web colours-im just going to use Tan and Green 
It is by no means a comprehensive guide just meant to be an easy way to identify what type of liner you have and does not include the early VERY VERY RARE pressed paper Hawley type liners or the liners with Rayon webbing etc as they are more for collectors(and i dont own any to take pics of 
)
WW2 LINER-All WW2 made liners are basicaly the same with slight differences in A washer colour, and HBT type depending on year of manufacture and maker but all basicaly similar in appearance.Most were made with a Tan hbt material cradle but i believe late war this changed to a Green colour.
KOREAN ERA-I believe late WW2 onwards the webbing used was changed from Tan to Green.Korean liners are EXACTLY the same as WW2 ones but will normaly have a Korean date stamped inside the crown.
EARLY VIETNAM-In around 1958 i think the liners were changed slightly.Cradle material was changed from the HBT used in WW2 and Korea to a harder wearing Cotton Web material.Liner remains almost identical in looks to the WW2 one but doesnt have the small grommet/hole at the front that was used to attach rank badges etc.
VIETNAM-Biggest change was during the war when the liner was changed completely.The liner material was changed to a different thicker material that offered greater ballistic protection and usualy came in a orange or green colour when new was quite bright 
.I do have but cannot find at the moment a Nam era liner made with a WW2 type fibre shell so might have been a transitional one??
While these look nothing at all like WW2 ones from the inside it is possible to rig up a leather liner chinstrap to use as a WW2 type liner.
POST VIETNAM TILL THE END OF THE M1-Late 70s till the M1 was taken out of service in the 90s the liner went through one final change.Basicaly it remained the same as the Nam type one but instead of the web cradle being attached to the liner shell by rivets making it almost impossible to repair,the cradle was no attached with pop studs so could easily be replaced if damaged/worn out etc.
I do have one of these somewhere but cannot find at the moment.
Hope this is of help and as i said ONLY A BASIC guide of infantry liners
Nice guide I will have to have an other look at mine now. 
Free speech is expensive these days!
