I know what you may be thinking, "What are jeep caps?" Well, they're the unofficial name for the wool cap that Radar was known for wearing... unofficial, because that's simply what troops started to call them, it's military name was the M-1941 cap.
![Image](http://i91.photobucket.com/albums/k290/snowthbo/jeeppic.jpg)
Anyway, the jeep cap originated in the winter of 1941-1942 for troops to wear under their steel pot helmets as a liner, to give them extra padding and extra warmth while fighting in the frigid cold, however, the cap quickly grew in popularity with the troops for it's casual and relaxed look, so many soldiers started wearing it by itself, even though it wasn't designed for such use. In fact, I understand Patton and other officers hated the caps because they looked unmilitary, so they were gradually phased out and replaced with the standard-issued field cap shortly afterwards to make uniforms look more, well, uniform.
While M*A*S*H was set in the Korean War, Radar wore a jeep cap, which Gary Burghoff personally picked out when deciding on Radar's wardrobe to help establish the character (along with over-sized fatigues, boots one size too large for his feet, the glasses, etc.)
The jeep cap saw more exposure during the first season of the show, occasionally, an extra would be seen wearing one, such as an African-American extra who was seen in a handful of the earliest episode; this actor (along with Roy Goldman) was also an extra on HOGAN'S HEROES, where he still wore his jeep cap (I'm assuming the actor kept it when HOGAN'S HEROES ended, then wore it again while on M*A*S*H):
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-92161_zps16c87f7b.png)
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-178659_zps162adc36.png)
Young-Hi, the titular character of the episode, "The Moose" (1x05) wore one as well, when otherwise not wearing a helmet:
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-94253_zps37f2847e.png)
But perhaps, the most we've ever seen these caps on M*A*S*H was the episode, "Dear Dad" (1x12), as numerous different extras are seen in camp wearing them:
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-97210_zps83a2babf.png)
Not only that, but many of the guest characters wore them as well, including three different nurses Hawkeye was seeing (the lovely Barbara Bannerman being one of them):
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-96616_zps670667d0.png)
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-97928_zps7e756380.png)
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-139186_zps8f953aa7.png)
A soldier and his wounded comrade:
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-141661_zpsae22a662.png)
Even Klinger wore one (inside out, for some reason)
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-141448_zps8c17bfee.png)
Afterwards, it seems like Radar became the only one who wore a jeep cap, which I wonder if it was intentional or not, as it seemed like they always looked for ways to make sure each character stood out and was distinguishable from the others, however, it still made occasional other appearances; the tanner and blonder Nurse Gage wore one in "Out of Sight, Out of Mind" (5x04):
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-153952_zpsb7adbc7f.png)
And even B.J. and Kellye each wore one in "Twas the Day After Christmas" (10x10)
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-175348_zpse9e18e0e.png)
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-176103_zps830cbea0.png)
Radar himself seemed to go through a few replacement caps over the years as well:
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-90967_zps2776f329.png)
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-151704_zpsd1122095.png)
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-155842_zpsbe111aaa.png)
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-158074_zps8abf1152.png)
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-166955_zps2c0106af.png)
One of the features of the jeep cap is that it has ear flaps around the cap, which can be pulled down over the ears as needed for extra warmth, and one thing I found somewhat peculiar is that during cold-snap episodes, Radar rarely used them, maybe only doing so a couple of times,
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-144725_zps81ed1106.png)
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-168492_zpsfe809946.png)
Otherwise, he seemed to wear either makeshift earmuffs from the communications headphones and toilet paper, or actual earmuffs (I wonder why):
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-145274_zps26e8919e.png)
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-148877_zpsed3e296d.png)
![Image](http://i91.photobucket.com/albums/k290/snowthbo/vlcsnap-170161_zps3bcce733.png)
I actually own about four jeep caps in the original WW2 design.
![Image](http://i91.photobucket.com/albums/k290/snowthbo/jeepcaps.jpg)
The two on the inside are actual WW2 originals I got from eBay, the outer two are reproductions designed to look like the originals. The second one from the left is supposed to be a size large (the caps originally came in four sizes, since yarn wasn't as stretchy or elastic back then), but the seller neglected to mention it suffered some significant shrinkage, it doesn't fit at all; the second from the right (with the white paint stains) is a little larger, but still a shrinky-dink, when worn, it looks almost like an olive yarmulke. The one of the far left is a repro I purchased a couple of years ago... it wears well, but it's not a well-made repro; the one on the far right I purchased about five years ago (ironically from the same person), and it's awesome, I wear it all the time (as you can tell by how faded it is), it fits well, and looks just like the originals.
Since Radar made the cap popular, the army started manufacturing them again, however modern-day jeep caps really look nothing like the originals (and I also have a modern-day surplus jeep cap, not pictured though). I unwittingly started a trend in my town several years back, now every fall and winter, several people can be seen walking around in jeep caps of different designs and colors (which kind of makes me feel robbed of my individuality, even though I've only seen one other person, whom I assume was a vet, wearing one made in the original WW2 design
![Razz :P](./images/smilies/icon_razz.gif)