These switches are for use with the automatic standby generators we sell (or in some cases portable generators) and should be installed by a qualified electrician or electrical contractor.  Local permits may be required. Remember that the transfer switch current rating must be at least high enough to carry full rated load of your generator.  It also must match or exceed the current rating of the upstream breaker or fuse protection that will supply normal utility power.  Most jurisdictions do not require the transfer device to switch the neutral.  Therefore these prices do not include the extra pole for that purpose.  If your local codes or application requires the neutral to be switched contact us for a special quote.