The best place I found awhile back for the holster shirt was the NRA store. It will be hot, the is a ton of padding under each arm and the pocket is large enough to store a Desert Eagle 50AE. Any Kahr would be lost in it. That being said it works. I have one, I rarely wear it, it just doesn't feel right.
I'd try to go slightly tight if you try one, I think that would help.
One officer wore one bowling with a unbuttoned shirt over it. He went to toss the ball and the gun followed the ball about half way down the lane. I honestly don't see how that could have happened, they seem much more secure but I guess being bent over and the sudden stop could make it happen.
He walked down and picked it up, no questions, no problems.
Most fanny packs have a little string sticking out one corner that you pull to open the pouch, don't really have to unzip really. Not a great deal but to me somewhat better than velcro which announces to the whole world that your opening something.
In Memory of Paul "Dietrich" Stines.
Dad: Say something nice to your cousin Shirley
Dietrich: For a fat girl you sure don't sweat much.
Cue sound of Head slap.
RIP Muggsy & TMan
"If you are a warrior legally authorized to carry a weapon and you step outside without that weapon, then you become a sheep, pretending that JOCKO will not come today."