We offer 3 MyTag GPS Locators, XTraK, XTrakR and XPress. 

They all do basically the same thing - tell you where your loved ones and assets are, and if they move. 

The biggest differences between the models are: 

MyTag XTraK is waterproof and rugged.  It has a 3 year battery life, so you never need to worry about it.  Its ideal for assets like boats, caravans, trailers, cars, motorcycles, jet-skis, anything that might be stolen 

MyTag XTrakR is also waterproof and rugged.  But it has a rechargeable 3 month battery and also has indoor wifi positioning technology.  Its great for kids, elderly parents, bikes, cars ... anything where its okay to recharge the unit once in a while. 

MyTag XPress does the same as XTrakR, but is extremely light, and is not waterproof.  Its great for luggage, cars, kids backpacks, lone worker monitoring, parcel tracking - anything that isn't likely to get wet. 

A full comparison is here: XtraK, XTrakR & XPress Compared