Peru operates on a 220V supply voltage and 60Hz., so visitors will need a converter for 110 volt devices like hair dryer, however keep in mind that most cellphones and computers have this converter built-in, and therefore there is no need to bring an adapter for such electronic devices. Most plugs in Peru are the two-pronged flat type found in the US, but a three-pronged (with ground) and a two-pronged circular type are also found.
The electrical outlets are Kantu Garden Lodge are dual and have both the two-pronged flat type found in the US and a two-pronged circular type, as well as a usb charger, like this:
You can read more about the electrical outlets in Peru here: peruforless.com/blog/peru-outlets/