What brand or kind of harness should i get for my parrotlet?

The Fether Tether makes a model for very small birds. I bought one for my cockatiel when he was seven weeks old, however, I could never get him into the harness. Birds generally don't like being restrained, and he thrashed so hard and fought me trying to get that harness on that I finally gave up. I was afraid he was going to hurt himself. Some birds (notably conures) are often more receptive to having their bodies manipulated, but if your bird isn't already used to having his wings stretched out by hand, etc. then you might want to consider getting a travel carrier instead to take your bird around. I'm not saying it's impossible, but it would take a lot of training and patience to get your bird to accept the harness, even if Charlie is still young and impressionable.