[exim] Just a quick one, relay from hosts

How can I set this up to allow the 192.168.5.x block?

Currently I am setting it like

relay_from_hosts = 127.0.0.1 : 192.168.5.26 : 192.168.5.51 : 192.168.5.18 :
192.168.5.106

Prob something simple, but brain has gone to sleep