1-2-3 Radiators are just like the name implies, EASY! Proform s new line of radiators and modular accessories all fit together just like they should. These aren t just your ordinary single pass radiators they offer beautifully tig-welded tanks with a slick looking profile design that is unique to Proform. These radiators also incorporate PROFORM s unique Four-Corner design that makes adding a shroud or bracket easy because all the mounting holes line up. All radiators are dual one-inch tube, single pass, with optimized louver design to maximize cooling, and deep draw headers for an extra solid tube/header seal. No epoxy or anything else like that just tight tolerances all around. Building your custom cooling system is easy: Stage 1 - Start by choosing the radiator that is the right width and inlet/outlet configuration for your vehicle Stage 2 - Choose a single fan or dual fan shroud or bracket that fits your radiator Stage 3 - Choose the correct fan(s) to match your shroud/bracket. To top it off, throw a fan controller into your package and you've just built yourself a really nice cooling system that's ready for the show, streets, or strip!