Air cleaner plug only. Required when you install a custom exhaust system in combination with a high flow or otherwise custom air cleaner kit. The exhaust plug (981567) is used to plug-off the stock wiring that runs to the mechanical actuator valve in the stock exhaust header; and will prevent trouble code triggering by the stock ECU. For the air cleaner the other plug (981570) is used to plug-off the stock wiring that connects to the sealed-off intake valve actuator (OEM 70991-07) located in the stock air cleaner housing of late H-D models. Again; this also will also prevent trouble code triggering by the stock ECU. Used on H-D models; equipped with a mechanical actuator valve inside the exhaust only. Note: See 981567 for the exhaust plug only. **This Dynojet product is not available for purchase by dealers located in the UK**