In order to determine the type of adapter you require, you need to know whether your device is 2- or 3-pole (i.e. earthed or unearthed). Apart from a few exceptions, the difference is easy to recognise on the plug: 2-pole device plugs have two pins; 3-pole plugs have three pins.
You can find an overview of 2- and 3-pole devices here.
The SKROSS World Adapter Classic, EVO and MUV series are designed exclusively for use with 2-pole devices. All our other adapters support both 2- and 3-pole equipment.