The Advanced Accessory System PC Connection Kit includes: PC Serial Port Cable with DB9 Connector, 9V Power Cable and detailed instructions. The PC Connection Kit requires: PC Serial Port, 2-9V Batteries, HumminbirdPC Software (from humminbird.com). If you have only USB communication ports on your PC or laptop, see our part AS USB which will allow you to use the AS PC2 on these type of setups.