If you're switching to Speed Density in your DSM or Evo 8/9, you'll need these sensors to get you on your way. The STM GM Speed Density Sensor Kit is a much more affordable alternative compared to AEM and includes the GM AIT sensor, matching harness and aluminum weld bung for your intercooler pipe with a 4 BAR Omni Power MAP Sensor. Vehicle Fitment: 2003-2006 Evolution VIII IX 1990-1999 Eclipse GST/GSX 1990-1998 Talon TSi 1990-1994 Laser RS Includes: (1) STM Aluminum 3/8" NPT Weld Bung (STM-FAB-3/8-ALFB) (1) Omni Power 4 Bar MAP Sensor (MAP-MITS-4BR) (1) GM AIT Sensor (25036751) (1) STM Pigtail Harness (STM-HAR-AIT)