Proflow's new LS billet thermostat housings not only look good, they also come with a new high temperature Viton o-ring design, which means you don't need to use old rubber seal. They suit a standard 56mm diameter thermostat which is the same as the original LS2/LS3 versions.

 

Proflow's new LS billet thermostat housings not only look good, they also come with a new high temperature Viton o-ring design, which means you don't need to use old rubber seal. They suit a standard 56mm diameter thermostat which is the same as the original LS2/LS3 versions.