Source Nat without IP Range

Hi,

What is the proper way to SNAT an IP to another IP? I don't want to use the external interface IP address but the system asks to enter the IP range when I select Dynamic IP Pool instead of a single IP Address. How to do "one-to-one" nat without using an IP Range?

For Example, 192.168.1.10 should be translated to 10.10.1.10 before leaving a DMZ Interface.

Thanks.