Large hack saw blades?

[wantacoe]

I picked these up recently. They are 14" long, 1 1/4 tall and .065 thick. Apex and Karflex brand. How old are these?
Were they used on a regular hack saw or are they some kind of industrial blade? Thanks for any info.

 

[The Cobbler]

probably used on a power hacksaw , pretty much been replace by band saws now adays

 

[neophyte]

There are still hand held power hacksaws, that use the giant blades, although with a few holes in one end for mounting.
Fein and at least a few other companies make the powered hacksaws, in electric and pneumatic versions.
Powered stationary hacksaws are also still manufactured new.
I presume most of the power hacksaws are made for larger blades, but plenty of the smaller saws still exist, so blades are still sold.
Also, the blades are likely just made in long lengths, and then cut down to the length necessary, so making shorter blades isn’t really that muck of an issue.

 

[RTM]

. How old are these?
Were they used on a regular hack saw or are they some kind of industrial blade?

I have some that were supposedly from a power hacksaw. Supposedly make great knife blades. I have three different tooth patterns, all about that size.