I am making a small cooler box using a Peltier. At first, I used a Tec1-12706 without researching first, and it barely went under 12 °C at the cold side. I need a Peltier module that is 40 mm x 40 mm that is 12 V that goes to at least under 0 °C. I have looked at ~ 20 modules, but no matter what, none tell you how cold it can get. It just says Q<sub>MAX</sub> that just says at what voltage it is when it is the coolest, but never say temperature. 

How can I find a Peltier module that matches my specifications when it is not listed in the datasheet? Can I convert it from some other parameter?