Haltech Nexus S3 Plug 'n' Play Adapter Harness - Nissan Skyline R32/R33/R34GT-RProduct Details If you are using a factory harness and are after an easy ECU upgrade, take a look at Haltech Plug 'n' Play Adapter Kits. These adapters plug directly into your Haltech ECU and have a set of factory connectors on the other side which plug straight into the factory harness. A simple Haltech Plug 'n' Play product that allows you to be up and running in just a few hours. The quick start guide will walk you through installation of the