RFID Placement: HeadlightSticker Rule of Thumb

In Support by Raymond Jackson

We’ve covered how important it is that the angle between your RFID credential and the antenna is, by far, the most important factor to successful reads.

Where sticker placement is concerned, here are the guidelines:

  1. Place the sticker horizontally.
  2. Place the sticker at least 2 inches from materials containing metal whenever possible.
  3. Place the sticker so that it faces the antenna.

1. Place stickers horizontally

Stickers must be placed horizontally.

Don't mount HeadlightStickers™ diagonally or vertically. It looks bad and won't work.

Don’t mount HeadlightStickers™ diagonally or vertically. It looks bad, and it won’t work.

2. The Two Inch Rule

The two inch rule is easy enough, and possible to follow on all but the smallest of headlights. We include an install card in every box of HeadlightStickers™, and that card has a two-inch ruler for your convenience.

Make sure to place the HeadlightSticker™ at least two inches away from any metal, when possible. A two inch ruler is included on each install card, with every box of HeadlightStickers™

A two inch ruler is included on each install card, with every box of HeadlightStickers™ to help you find a great spot.

Sometimes it won’t be strictly possible to follow the two inch rule. Maybe that smart car’s headlights are a tad bit too small to have two inches on any side of the sticker. If that’s the case, do your best to center the sticker as far from the metal as you can. Read range may be effected a little bit, but it shouldn’t be too bad.

3. Stickers Facing Antenna: The Rule of Thumb

The goal is to face the sticker face-to-face with the antenna at the point it has to open the gate.
It sounds intuitive but can be a fairly complex three-dimensional problem.

Fortunately, most of us have a great tool for quickly assessing the directionality of a sticker: your thumb.

Stick your thumb on top of the center of the sticker to see where it is pointing.

Stick your thumb on top of the center of where you want the sticker. Does it point toward the antenna? You’re good to go!

The HeadlightSticker Rule of Thumb is a super easy, intuitive way to get your sticker to face the antenna.

Getting Started: Where is your antenna?

When assessing where to place a HeadlightSticker™ for optimal efficiency, it is essential to know where the antenna will be, relative to the entering vehicle:

  • Is the antenna on the left or right side?
  • Is the antenna down low by the barrier arm, or mounted on a six foot pole?

Question 1: Which side?
This one is common sense. If the antenna is on the driver’s side, place the sticker on the driver’s side headlamp. And vice-versa: if the antenna is on the passenger’s side, place the sticker on the passenger’s side headlamp.

If the antenna is on the driver's side, mount the HeadlightSticker on the driver's side headlamp. And vice versa.

If the antenna is on the driver’s side, mount the HeadlightSticker on the driver’s side headlamp. And vice versa.

Question 2: How high is the antenna?

A typical sedan may not have many options, but vehicles with large or complex headlight shapes have more options for placing the HeadlightSticker. In such cases, you may want to place the sticker on a fairly front-facing part of the headlamp (for a lower antenna) or toward the top (for a higher antenna.)

Here is a great time to use your rule of thumb to find a place where your HeadlightSticker will point at the antenna. Keep the base of your hand flat against the headlight, and point your thumb out. If your thumb points toward where the reader will be, you’re good.


A more standard-shaped headlight doesn’t give you many options to go up or down — but for a particularly angular headlight you should take care to consider antenna height.


This vehicle has very angular headlights, offering several possible mount points. Pictured above is an upward facing mount point to meet a high mounted antenna.

Tips for the Rule of Thumb

When using the Rule of Thumb to figure out the best point for mounting a HeadlightSticker, it is important to do so from where you want the read to happen.

For instance, if you want the arm to open only a vehicle is right in front of the barrier arm, you’ll want a high mounted antenna pointing downward. Then you would want to put the sticker as high as possible.

Or if you want a long 30-40 foot read range for a gate, a low reader is ideal, and you want to use the Rule of Thumb from that far back to position the sticker.

When you are ready to install the sticker, park the vehicle in the target read zone if you can. For wherever you’re planning to install the sticker, double check with the Rule of Thumb: does your thumb point at the antenna?

If so, the read will be optimal when the car is at this particular location. If not, move your hand and find a spot that works better.

Suboptimal Positioning

Keep in mind that the rule of thumb is intended to find the best place for a sticker at a particular vehicular position. If you follow the rule of thumb, you all but guarantee success.

Of course, RFID transmits out in a burst, not a straight line. The Rule of Thumb helps you find the center of that burst for the best read rate. Don’t sweat it too much if it isn’t exact.

View instructions for installing the HeadlightSticker!