Most guitar effects pedals do not include power supplies, as it is common practice to use a dedicated power supply with multiple outputs to power multiple pedals at once. 
 
If you are only using one pedal on its own, check the instructions and see if it takes batteries – this can save having an extra cable hanging around unnecessarily! 
 
If you are looking to buy a power supply, you need to check the power requirement of the pedal, as well as the type of power supply it requires. Most guitar effects require a 9 Volt, Centre-Positive supply, however, the amount of current will vary between pedals. 
 
The power requirements should be specified in the product manual, or on the pedal near the power socket.  
 
While the polarity and voltage need to be exact, the current needs to be the same or higher – if a pedal is not getting enough current it will not work correctly, if at all. 
 
PLEASE NOTE: Using the wrong type of power supply can cause damage to your pedals, and as such, if you are not sure which power supply you require, please raise a support ticket and our customer service team will be happy to advise you further.