Advanced power strips (often surge protectors) can be a useful means for saving energy when used in conjunction with home entertainment and/or computer systems, allowing power to be automatically cut to non-essential devices when not needed. As many electronic devices continue to draw power even when off, cutting power at the outlet maximizes savings. Most energy-saving surge protectors have 2 always-on outlets, a master (control) outlet, and 2-6 controlled outlets that automatically turn off or on as the master appliance is turned off or on.