Both the Emag and Xmag have three modes of operation. Mechanical mode(selector switch lever in the 9 o'clock position and the battery off)(operates without the electronics), Electronic mode(selector switch lever in the 6 o'clock position and the battery on)(operates like a normal electric marker with a magnetic switch), and Hybrid mode(selector switch lever in the 9 o'clock position with the battery ON)(trigger is actuated electronically with a mechanical trigger response).
There's the Emag and ULE Emag. When the Emag first came out, it was heavy(bout 3.4lbs.). Now with all the ULE(ultra light engineering) parts, you can upgrade to, or buy a ULE Emag which performs the same but at almost a full pound lighter (bout 2.5lbs.)
The Xmag(2.7lbs without barrel) is pretty much the same thing as an Emag cept for a few details. The biggest difference lies in the aluminum body with interchangeable breeches(accepts cocker threaded barrels). This takes the place of the standard body and rail for the Emag. The Xmag also has an adjustable A.C.E. with an on/off switch.