I love this thing! It's under 3.4 ounces and you will never have to worry about being out of cell tower range. It has buttons for Check-in and SOS. It works with smart phones to get weather, maps, and send & receive texts from anywhere in the world. They offer reasonable monthly or yearly subscriptions. It works on credits. Each credit is one text message, basic weather report, or map download. You have to start with the Plus Plan for 4 months that is $34.99 The Basic plan is only $14.99 a month for 20 credits with $0 activation fee. If you are going to be in the mountains, always want to be able to communicate with your group or kids, then you need this!