question about circuit breaker

[mn12471]

I have a circuit that has a 3amp 125V slow fuse (3AG).  I want to replace this with a circuit breaker, but I'm not sure how to find an equivalent part.  Would a "slow-trip" 3A breaker be the same? 

Thanks
Eric

 

[Hero999]

A thermal circuit breaker would do.

 

[enggricha]

Depends on your application, what is the fuse protecting?