NAL Shout Nano is a handheld, global two-way communications device for communications and personal tracking.
Shout Nano is much smaller and lighter but also more manageable than NAL Shout.
The device uses Iridium Short Burst Data (SBD) service to provide location information generated by GPS receiver, send and receive status reports and messages as well as emergency and warning messages.
The device is extremely power efficient which means that on a single charge, you can send 1 report every hour up to 2 months (about 1200 reports).
Read more here.