Our engineering brains have excelled themselves with this little baby.  The PL17 is one of the only torches currently on the market that offers a wide voltage range circuit - in English that means it can run on either a standard or a rechargeable Lithium battery, the latter offering higher voltage.  But they couldn't simply stop there.  Via the rear tactical switch the user can select between six settings of light: full-power, half-power, quarter-power, fast strobe, signal strobe and SOS. And incredibly, they managed to house all this within a compact 8.5cm body.