The TK05R makes the most out of its compact size: thanks to a high-quality LED element, APF technology and a precisely designed reflector, it has a range of nearly 500 meters. It's a great choice for both recreational and professional use. With the tactical switch (the larger switch), you can select a momentary-on mode by pressing the switch halfway. Pressing it fully activates continuous mode. The function switch allows you to instantly select a blinding strobe mode when the flashlight is off, or when the flashlight is on, you can adjust the brightness (low - medium - high). The Fenix TK05R utilizes APF pulse signal technology. The combination of small size and high power is largely due to APF technology. It also enhances the flashlight's ability to resist external interference, such as strong magnetic fields and other disruptions. - The 1100 mAh rechargeable battery is replaceableif you wear out the battery with heavy use or need multiple batteries for a long trip, you can easily