In For A Few Dollars More Blondie wore a wrist brace on his right arm. It did not reappear in A Fistful of Dollars or in The Good The Bad and The Ugly.
In reality the wrist brace was the property of the film's leather maker Andy Anderson who wore it daily in real life due to a WWII injury. Sergio Leone saw Andy Anderson wearing it, liked it, and talked him into letting Eastwood have it for his character because he thought it looked cool. Presumably Anderson made a new one for himself to replace it with.
If you look closely you can see Andy Anderson's Ace of Spades logo embellished on the inside face of the brace.