The Simple Squared is the easiest to use pen battery on the market.  Simply click the button 2 times and it automatically preheats for 10 seconds. The S2 can then either be breath activated or button activated. 

The square body ensures that your battery won't roll off the counter or behind your dresser. Most batteries lose performance as the battery power decreases. So we upgraded the technology to give you consistently power output within a tight range, regardless of charge state.

Features:

2 click on/off

Female threading for male threaded attachments

Breath or button activated

400 mAh battery capacity

USB-C charging (cord included)

Dimensions:

Length: 4.1"

Width 0.45"

Weight: 0.9 oz

*this is the replacement battery for the Simple Squared flashlight.  It works with our other threaded accessories such as the hot knife and many other threaded attachments from other companies.