Doe anyone know what this is made for?

[Fishaholic]

Found them in an old tackle box I forgot about.  Anyone know how to use them?

[scout/sniper]

Hook the line from your pole to the eyelet.
Trail a hook and bait behind it from the snap ring.

I can't tell from the pic what size it is, but I use a larger 2 spinner model for trolling for kokanee.

[wildmanoutdoors]

I wonder if those were made by Hildebrant?

[Dhoey07]

I use them trolling on Roosevelt for rainbows with a fly about 12" behind them.  I use a little larger size though

[deltaops]

Send all your tackle to me and I will test it all out and let you know how it works. 

Seriously, what a couple others have already said.   You can use them for just about anything really.

I used the ones I had for kokanee. Pretty much what Scout/Sniper said.

[scout/sniper]

Send all your tackle to me and I will test it all out and let you know how it works. 

Seriously, what a couple others have already said.   You can use them for just about anything really.

I used the ones I had for kokanee. Pretty much what Scout/Sniper said.

Like you said, they are good for a lot of things.
I always take several out with me.

[Phobic]

My son and I have done really well with small ones of those fishing for cutthroat. Had a blast.

[KFhunter]

get a small deal of brasso and a rag - buff up those blades.

the flash will travel much further in the water

[ICEMAN]

Been using those since I was a wee little lad. Drag a fly or bait a distance behind them. Awesome light tackle gear.

I have a few with  mother of pearl type blades that work well too. A great addition to your light tackle.