As you may have seen, most UPS units are fitted with IEC320 C13 mains output
sockets. These are the computer-type or kettle lead-style connections, and
are rated up to 10 Amps:

Some UPS units also use IEC320 C19. These are the 16A rated version:

While
the C13 connection is suitable for connecting up most PCs and similar devices,
they are not suitable for equipment that has a standard 13A UK plug (also known
as BS1363A), such as many of
the smaller routers and wireless devices, or units that use a low-voltage
adapter. In larger systems where UPSs are supplying power in cabinets,
Power Distribution Units can be used to provide multiple UK outlets from a UPS
feed. However, for smaller requirements, we can supply a four-way UK
outlet adapter that will plug into a UPS C13 socket. This low-cost unit, part
number F6C104UKPP-A, can be ordered with a UPS or as an accessory -
here.
There are also a few UPS units that have UK plugs as standard, but these tend to
be quite small load units with short battery run times. In most cases they
do not have automated shutdown capability. This ES range of
UPSs can be found
in the BackUPS section -
here.