AKOray
AKOray is a budget brand of lights with a simple cylindrical shape and a wire clip. The lights also say P.D.C. on them so this could be a company name. Some lights in the AKOray family are nearly identical to lights by other brands like UltraFire and Trustfire.
It is unclear if AKOray is a brand and, if so, of what company. However, there is a line of budget lights called AKOray that seems generally well-liked.
Lights
All AKOray lights feature a natural color of anodizing that can vary from greenish-silver, to bronze, to green. They also include a wire clip that attaches to holes in the very thin tail piece (does not affect watertight integrity) that is unique in that the tail threads into the body (usually it is the other way around with the body piece threaded on both ends and therefore the tail piece is thicker). All have a reverse tail clicky.
K-102 - 1xAAA/10440 1-mode light. This version seems to have been discontinued.
K-103 - 1xAAA/10440 1-mode light.
K-106 - 1xAA/14500 5-mode, 6-mode, or 3-mode programmable light. See instructions below for the programmable version. The 5-mode version has inconsistent quality and at times can be very overdriven and incredibly bright or not. The Trustfire F20 is a clone of the 5-mode version. Review: jayki, sb56637, brted
K-109 - 1xCR123A/16340 5-mode, 6-mode, or 3-mode programmable light. If programmable, use the instructions below. The UltraFire A1 is a clone of the 5-mode version of this light.
AK-12 - 1x18650 1-mode light.
AK-16 - 1xCR123A/16340 or 1xAA/14500 3-mode programmable light (see instructions below). The battery chamber of this light has plastic sleeves as the top and bottom that a AA battery can fit into, but will hold up a CR123A battery. Long springs in the top and bottom ensure a good electrical contact with either type of battery. Review: old4750
AKOray 3-mode Programmable Instructions
The programmable lights all have 3 modes and mode memory. Each of the 3 modes can be independently programmed to brightness levels between 8 and 200(ish) lumens, a varying strobe rate, SOS, or a double-blinking mode. They also feature optional low battery protection for lithium-ion batteries.
The K-106 was originally available from DealExtreme who described it as a 6-mode light, but people soon figured out that it had 3 programmable modes. At some point DealExtreme started shipping a true 6-mode light. The 3-mode programmable K-106 was available from KaiDomain for a while after that, along with KD's versions of the K-109 and AK-16 which are also programmable, but the K-106 they are selling now are no longer programmable.
Instructions are also available in this CPF Post.
Setting Modes To set modes, turn the light on and half-press the power button 5 times. The light will flash once to indicate that you are programming Mode 1. To store the mode, half-press the power button during the ramping sequence. The light will ramp from dim to high fairly quickly, then flash off and remain on high for a few seconds. This is followed by the beacon modes (double blink), then a ramping strobe from slow to fast, and finally the SOS mode. After half-pressing the switch to set Mode 1, the light will blink twice to indicated Mode 2 and go through the ramping sequence again. After setting Mode 2 with a half-press the light will blink three times to indicate Mode 3. To set Mode 3 and store the settings, instead of half-pressing (which would return you to Mode 1) just turn the light off for 5 seconds to set the mode.
To get the best low, it is probably easier to program Mode 1 to High first, then set Mode 2 to Low and Mode 3 to Medium. After setting Mode 1, the light will flash twice. Wait until right when the ramping starts and half-press. If you press before the ramping sequence, the Low will be a little higher than you can set yourself.
If you like how some of the modes are and just want to set one or two modes, you can do a half-press right after the flash for the mode you want to keep and it will be saved at the old setting. However if you skip two modes and set another one low, the three quick presses may accidentally trigger the factory reset (see below).
Battery Protection To set battery protection: turn the light on, then quickly half-press the switch 3 times. If the light flashes once, then the protection is off. If it flashes twice, the protection is on. The protection works by dimming a bright mode after a second. If you are using NiMH or alkaline batteries, and protection is on, the bright mode will always dim until you turn protection off.
Factory Reset To reset the light to factory settings, half-press 5 times to enter programming mode. After the light flashes once to indicated Mode 1, half-press 3 times quickly. The light will then be at full brightness. Turn the light off for five seconds to store the factory settings.