Aug 09

Xenon Depot Xtreme LED H4 headlight kit review

PNP LEDs have a stigma around them, and for good reason. Installing HIDs or LEDs in halogen housings has historically been a controversial move because performance has always suffered. Whether it?s glare or total lack of visibility, PNP has never been the answer.

But times are changing, and LED technology is advancing quickly. Philips released a PNP H4 LED bulb that performed well in most housings, and from there PNP LED tech blossomed.

The Xenon Depot Xtreme LEDs use tiny Philips LumiLEDs to emulate a halogen filament to retain proper performance in a halogen housing. Adding to the ?standard? Philips design, everything (including the circuit board) was blacked out to reduce reflections. There is a flexible anodized copper heatsink on the back for passive cooling, foregoing an active fan. Fans, while providing superior cooling, add another point of failure, noise, and electromagnetic interference.

The bulbs come with an allen key to adjust the clocking and four zip ties to clean up the wiring.

Build quality:

Like most LEDs, these are extremely well made. They?re hefty, solid metal. The H4 plate is well made and fits into the headlight perfectly. The driver is compact and has loops for a zip tie to go through. All the wires are thick yet flexible. The H4 connector is of excellent quality and the connection between the LED and the driver is waterproof with a screw on retainer. There isn?t a thing I could criticize in terms of build quality.


The installation of these LEDs is much like a regular halogen bulb. You?ll have to slightly pull the retaining clip around the thicker body of the bulb and mount the driver somewhere, but it?s a fully plug and play installation. Stretching the rubber cap around the heatsink and body may cause you some trouble but the body is reasonably slim.

Be sure to fluff out the braided heat sinks after the installation is complete. This will allow for enough airflow to pass through them, cooling down the bulbs. They?re very flexible so they will fit in even the tightest of spaces.


This will vary between vehicles and this test was conducted on an OEM Toyota headlight from a 2000 MR2 Spyder. With its large round reflector, it generally takes well to quality LEDs.

These LEDs are clockable, and this will become important to get the ideal beam pattern. You?ll want to loosen the two set screws enough for it to rotate with a bit of force. You want some friction so it doesn?t come loose. Install the bulb, rotate until you get the ideal beam pattern, then carefully remove without moving the plate. Tighten the set screws and you?re good to go.

In these housings, performance was fairly good. While the output became messier and spottier, the overall beam pattern was retained. The hotspot was strong, the foreground was minimal, and glare may have actually gone down. The color is a pure white, with no yellow or blue tint whatsoever. It?s actually warmer than many OEM LED setups.

The hotspot became far stronger and wider, which should translate to better distance vision. The width was slightly increased as well. Surprisingly, there was no increase in foreground light, which would normally be a classic characteristic of PNP LEDs. A bright foreground causes your eyes to adjust and your pupils to shrink, lowering your overall visibility.

Unfortunately, the cutoff isn?t perfect. It became a bit wavy, though it remained intact. In my opinion the output remained perfectly safe and usable in terms of glare and cutoff.

High beam performance remained very similar. It might have become a little more diffused, though intensity remained good.

While Philips used three diodes per ?filament,? Xenon Depot opted for four. While this does increase brightness, the length of the line of diodes does exceed the length of an H4 halogen filament and thus does scatter some light. It could be said that removing a diode from each ?filament? could have helped the output.

Heat dissipation:
In my opinion, the braided heat sinks are not an ideal way of dissipating heat. While the body of the LED got hot, the heatsinks stayed warm. The difference in temperature was significant after 10 minutes of running. Fortunately, the bulbs don?t seem to have a problem with overheating.

While not perfect, these LEDs perform admirably in these housings and should perform reasonably well in others. Is it going to replace a retrofit? Absolutely not. But with so many people buying cheap LEDs that glare and perform poorly, this is a great alternative without breaking the bank on genuine Philips bulbs. As much as lighting enthusiasts might not agree, a safe PNP bulb is a good thing for the everyday person who just wants a nicer look and output.

You?ll get the benefit of that pretty white light, potentially improved output, instant on, and better longevity. The downsides are a potential decrease in output (depending on housings) and price. But with the latest price drop, they?ve become almost as affordable as the generic stuff on eBay.

If you?re dying to get that cool white light and a bump in output in a PNP package, this is it.