S&W model 63 kit gun

[mac1911]

can you tell me what the "kit" applies to ?

 

[Len-2A Training]

from:
http://world.guns.ru/handguns/hg105-e.htm

Kit Guns
The "Kit Guns" are longer-barreled modifications of the basic designs, intended for back-packers and others, who need a lightweight gun with a little better accuracy.

from:
http://findarticles.com/p/articles/mi_m0BQY/is_19_46/ai_65017380/

The steel revolver which once rode in every pack and tackle box has given way to one of aluminum and titanium -- much to the delight of hikers, campers and fishers everywhere.

Between the two World Wars fishermen and hunters used kit bags to carry their outdoor necessities, which often included a small handgun. Right after the .357 Mag. was introduced by S&W in 1935 as "The World's Most Powerful Revolver," the company went the other direction and brought forth the compact model of the .22/32 Target I-frame revolver called the .22/32 Kit Gun. The name came from the fact that this little .22 was designed to be carried in a kit bag -- be it a hunter's, fisherman's, hiker's or backpacker's.