USB license key that holds up to 500 software licenses required to use plug-ins, DAW's etc. from certain pro-audio software developers such as Waves, Antares, Sonnox and the AVID Pro-Tools family of products aswell as numerous other manafacturers. Must be used in conjunction with the ilok website. After downloading the relevant software then you can then download your licenses onto your ilok USB key and use your Plug-ins that you have purchased on your computer, as long as your USB smart key is plugged in. (Please note if you lose the ilok USB key your licensed software will not load and you won't be able to use it, although you can buy insurance to cover this, please see the ilok website for more details), My experience was for the most part trouble-free but took a bit of time navigating various manafacturers websites after purchasing some Plug-ins online to get the various licenses on the ilok itself. When my license files were downloaded all the plug-ins loaded into my DAW (Cubase 6) with no problems. You can still use your favourite DAW without the ilok plugged in but you will not be able to load any of the ilok copy-protected plug-ins without a nag screen popping up and they will not load until you attach you ilok to your computer and click 'authorise'. My only problems with this device was the cheap plastic lid that has already cracked, may I suggest they make it out of stronger plastic in future! luckily not at all an essential part of the ilok, and the fact that all audio sofware manafacturers should come together and use only ONE universal USB license device, currently there are a few different ones required to use various pro-audio sofware and as each one uses a USB socket not at all practical to use with a laptop with limited USB sockets. I currently have a USB audio soundcard, USB keyboard controller, USB e-licenser for Cubase and now an ilok and only 3 USB sockets! Although I think the USB license keys may work using a powered USB multi hub (fingers-crossed).