Finally found a replacement that actually fits my HB66pro snugly — no loose connection like the cheap third-party ones I tried before. The 5V 1A output matches perfectly and it's been charging steadily for over a week now.

I was relieved this charger worked perfectly with my HB6560, since the output is exactly 5V 1A as listed. It’s nice to have a spare for overnight charging, though I do wish the cord were a bit longer for more flexibility. Overall, a solid replacement that does exactly what it should.