Motordyne plenum spacer
Aluminium plenum spacer with thermal management components(except basic version). Normally designed to work on any weather conditions either desert hot or snow winter cold without any overheating or condensation.
Basic - is a simplest version includes spacer only. Isothermal and Copper isothermal are differs on how they operate. In copper one there's a intake spacer made of copper for air warm-up while it's cold. Vendor says Isothermal is a good choice at warm climate, copper isothermal is designed to operate in cold conditions. So main rule if you it's cold in your region - copper isothermal is your choice, otherwise Isothermal would be enough.