A few weeks ago I released Airtool, a simple menubar app for OS X that allows you to easily perform 802.11 frame captures on a single or multiple channels. One of the options in Airtool lets you configure the link-layer header type you want to capture as part of the frames. In this blog post I'm going to give a brief description of the header types that are available for the built-in Wi-Fi adapter on a Mac so you can understand the differences and choose the right header type for your captures.