Here's why you need an adapter
The outlets and plugs used in Martinique are C, D & E. Take a look at the pictures below to see what each plug and socket type looks like.
Voltage and frequency Aruba vs Martinique
All outlets in Aruba provide a standard voltage of 127V with a frequency of 60Hz.Voltage: 127V Frequency: 60Hz
All outlets in Martinique provide a standard voltage of 220V with a frequency of 50Hz.Voltage: 220V Frequency: 50Hz