If you use a Remote, it is a very useful device to have if you like to blast. I have a limited number of these for sale. When they are gone there will be no more as they were discontinued due to slow sales. I currently have setups incorporating different combinations of these devices. My antifreeze kit when combined with an anti siphon tank is good within a temperature range of about 40 to about 80 degrees.
Tanks can become hotter than the ambient temperature.
I have measured mine at 120 degrees. The pop off valve will blow at about 130 degrees. For remote users, add the manifold to increase full auto shoot time before chilling the tanks. I also have some additions to the setups that will alleviate the annoyances of co2, such as having to remove the tank to de pressurize a dead gun, losing about 20 shots worth of co2 in the process and probably blowing an o ring, and having to choose between blowing an o ring or risking a partial cycle when de gassing the gun. These additions are not absolutely needed, but make using co2 a LOT more user friendly.