Banana to spade adapters

My speakers do not do spades very well. I am interested in buying a used set of cables with spade ends. Does someone make a high quality banana to spade adapter that I could use. The banana end would go into the speaker terminal and then I would connect the cable spade connector to the back end of the adapter. I think I have seen these before, but do not know who makes them. Any ideas? Thanks in advance for your help.
I know Apature makes such an animal. It is a dual banana plug & spades go between where the between the screw head on back & the metal body of the dual banana plug. Banana plugs are standard .5" spacing. Would imagine most single banana's or dual bananas with metal bodies work the same way. They should only cost $10-$15. If you're nice to your audio dealer where you purchased your speakers, he may give them to you at N/C. Just use care to buy a banana that fits the distance between your spades.
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the least expensive of these adapters can be purchased from radio shack.
Are the Cardas ones of the "locking" banana plug variety?