We use a special hose type with the ECU to prevent erroneous MAP readings which negatively influence how the engine runs. We've had customers in the past use cheap generic vacuum hose and have all sorts of tuning issues related to the hose expanding with boost, or sucking closed from vacuum so we offer this hose to prevent this scenario. This MAP hose is for people who need a replacement for the original hose supplied with the ECU because they poked a hole in it, bought the ECU used and didn't get the hose, or need a longer hose for a custom application. The original hose supplied with the ECU was 6 feet long. 

This is for all version numbers of the original PiMP, V1.0-V1.2.1 of the PiMPx & PiMPxs which all have the MAP nipple exiting out of the side of the ECU, as well as newer versions that exit right next to the EEC connector and use the smaller push lock hose. We ask for ECU type and version number so we can ensure you get the right hose type/size.