PCMCIA II card transmitter fits all notebooks and most PDAs When the PCMCIA card transmitter goes over the preset range, the master unit will sound a warning tone immediately Acts as a burglar alarm and a reminder Can be put inside notebooks or PDAs without other's awareness Offers safety, security and peace of mind Automatic battery saver function Auto power on and auto sleep functions Adjustable range setting from 0.5 to 8 meters An active wireless alarm Patented in the USA, Taiwan, Japan, mainland China and more Size: Pen type master unit: 4.3 x 1.3 x 0.5 inches (L x W x H) Sub unit: just like the real PCMCIA card type II Weight: about 70g Power: Master unit: 3VDC (AAA/UM-4 battery x 2) Sub unit: CR2032 lithium battery