K40 RLS2 Radar Detector Review

Following the traffic rules can get a bit tricky, especially if you live in an area with different speed limits or lots of traffic signals. The last thing you would want is to get a ticket for overspeeding.

As drivers, there are times when you forget to keep in mind those minor yet important on-road details such as speed limits. So to help you take care of this problem, K40 has come up with the K40 RLS2 radar detector model. Through this K40 RLS2 Radar Detector Review, you will know why this is one of the best radar detectors on the market.

What Is The K40 RLS2?

Sometimes you tend to jump a signal or drive at a higher speed in a hurry or just in the flow. What is worse is when you do not realize that there could be a police enforcement radar around that is monitoring your speed. In such cases, having a good radar detector in your vehicle is very important. This is why we bring to you one of the top-rated radar detectors – the K40 RLS2. It is handy, inexpensive, and recommended by many people.

The K40 RLS2 Radar Detector is a portable and compact unit designed for both two and four-wheelers. The unit has three different modes i.e., for driving in the city, highway, and urban areas. You can set the max speed limit to prevent you from overspeeding. Finally, coming to the installation, it is advisable to mount the device on the glass of the windshield for the best results.

Who Can Use The K40 RLS2 Radar Detector?

The K40 RLS2 is easy to install and ideal for those who drive a lot. It is suitable for people who do not know where there are speed detectors, especially in a new area, city, or town. This detector is perfect for both four-wheelers and two-wheelers because of its compact design.

What Is Included In The Box?

The box includes the main unit, a travel case, two power cords (one short and coiled and the other straight and long), and a suction cup mount. The box also contains a manual that gives you information on how to install and use the product. You also get a CD receiver that features the JVC remote app compatibility.

K40 RLS2 Radar Detector Review – Highlights

Here is a quick glimpse at the features that make up the unit:

  • This radar detector weighs only about a pound and measures 9.8 x 6.6 x 1.8 inches.
  • It comes with a wireless display feature.
  • The K40 RLS2 is perfect for people who drive fast, especially motorcyclists.
  • The device has three different modes for better coverage.
  • It is equipped to detect both radar and laser signals.
  • The manual consists of all the details you need to install and use the detector.
  • The design may seem smaller, but the device comes with all the necessary features you would need while driving.

Features Of The K40 RLS2 Radar Detector

The K40 RLS2 radar detector comes in a compact and stylish yet classic design. On the top part of the unit, you have built-in speakers and various buttons like – mark, quiet ride, mute, filter, and dim menu. The display may be small, but it is very much functional and easily understandable. Also, unlike other devices, this unit can detect laser and radar detectors.

Here is more about its specs in detail:

Different Modes

Speed limitations for driving within the city are very different from the highway or urban areas. The K40 RL2, however, is equipped with specially designed modes that you can make use of for improving your driving experience. The various modes include:

  • The City mode is ideal if you are in an area where there is no or minimal police radar.
  • The Highway mode is meant for highway driving as the unit can detect radar and laser signals easily.
  • The Filter mode is a special mode that can be used if you are traveling in a crowded urban area with lots of non-police radar signals.

K-Band Filter Of K40 RLS2 Radar Detector

This feature offers an automated and advanced filtering technology that intelligently recognizes and rejects radar-based false signals to help you focus on real threats. It also identifies other signals, including the KA band, X band, and laser frequency.

GPS Feature And Other Alerts

The K40 RLS2 comes with GPS features and thirteen other customizable settings. These settings include

  • Marking mute settings – You can use the mute setting to cut off or mute non-police or false alerts in areas where you travel frequently.
  • Marking alert settings – You will receive alerts when you travel in areas like school zones, dangerous intersections, and even red-light camera zones.
  • Quite a ride – You can use this setting under a pre-selected speed. The quiet ride option helps eliminate alerts when you are driving in a zone that requires you to travel at a slow speed than what you have selected. Enabling this function is ideal for speeds under 10 kph – 120 kph or 5 mph – 75mph
  • Speed monitor – K40 RLS2 speed monitor allows you to keep your eyes on the road by tracking your speed automatically.
  • Traffic sensor filter – This is beneficial, especially if you are traveling on the highway as it rejects alerts from traffic flow sensors.
  • Fully programmable radar/ laser alert options – Through this, you can eliminate visual and audible alerts to specific lasers or radar bands.

Display And Tone Settings/ Options

The display on this unit is of a decent size and gives you all the information you need. It also comes with customizable options so that you can change it as per your need. You also get the option to make changes to the alerts. The unit comes with buttons on the sides to increase, decrease, or mute the volume. Here are a few more choices that you get:

  • Dim option – You can use this option while adjusting the display intensity depending on your visual preference and time of day.
  • Tone or voice plus digital display – You get unique visual and audible warning alerts, especially if any police radar gun tracks your vehicle.
  • Vibrant dot matrix display – The radar detector’s display is easy to read and looks good and presentable. You can easily read it during the night and even at day time by adjusting its brightness. The default display settings include the speed reading, compass direction, and filter setting.
  • Signal strength indicators – You get to see numeric signal strength and audible Geiger indications.
  • RDD guard – The K40 RLS2 also protects you from Radar Detector Detectors (RDD) used by police or law enforcement officials.

K40 RLS2 Radar Detector Review On Programmable Features

Although there are some standard settings, you also can make changes to these to suit your particular needs. With the K40 RLS2 model, the different programmable features would include:

  • The voice type – female or male
  • Audio alerts
  • Wake-up settings – long and short start-up sequences
  • Speed display
  • Compass
  • Traffic Sensor Filter
  • Quite a ride
  • X, K, KA band and Laser On/ Off option
  • Factory reset

Additional Conveniences/ Services Offered

Customer support service

We all love that something extra when we buy a product this valuable. So the company recommends that you must contact their toll-free support system before you buy the product so that you can get professional advice if the unit is suitable for you or not. Even after purchasing the device, you can call up the customer support number for further assistance. The consultant will help you to customize your settings and even take you through all the available options.

Ticket free guarantee

The company provides a one-year No-Ticket or drive-ticket-free guarantee for those using this particular model. The manufacturer states that they will pay for your ticket if you get one while using the K40 RLS2 radar detector. This is great! But the terms and conditions of availing such a benefit include:

  • The ticket should not be a result of a DUI.
  • And, the ticket should not be issued in a construction or school zone.

How To Use And Install The K40 RLS2?

The K40RLS2 has a straightforward installation process. Yet, it is advisable to first read the manual before installing or using the device. As mentioned earlier, the box comes with a suction cup mounting bracket. So it is better to install the unit on the lower part of the windshield. This will give you more visibility, so you do not have to take your eyes off the road for too long. Once you finish with the installation, insert the power cord into the cigarette lighter’s power source outlet. And that is all!

You can read the instructions mentioned in the manual to customize your settings and better understand the various buttons on the unit.

K40 RLS2 Radar Detector Review – Pros And Cons


  • This K40 device identifies both laser and radar frequencies.
  • It covers a significant area because of the 360-detection feature.
  • The device also helps you to maintain your speed with its speed detector feature.
  • Based on where you are driving, you can use any of its three different driving modes for more convenience.
  • It is also compatible with the JVC remote app, Pandora, iHeartRadio, and Spotify.


  • Unfortunately, there is no update feature.
  • The K40 RLS2 is a little expensive.

Comparison Of K40 RLS2 With Escort Redline EX

Although the Escort Redline EX is a bit expensive, it is said to be the best alternative to the K40 RLS2. The Escort Redline EX features include the AutoLearn technology, intelligent false alert filter, clear voice alerts, nationwide coverage, and futuristic design. Moreover, it is also compatible with Windows 7.8 and 10. If the budget factor is not a problem, you can surely opt for Escort Redline EX instead of the K40 RLS2 as it is an advanced model.

Final Words

K40 RLS2 radar detector is indeed a useful device that comes with a compact design and provides exceptional sensitivity. It is portable and compact, making it ideal for both two and four-wheelers. This radar detector will make a perfect companion if you are a person who drives a lot in and outside of cities.

Its customizable settings allow you to make the necessary changes to accommodate your needs. The unit’s manual is a small handbook that consists of 20 odd pages and comes with various images to help you understand the device and its features more extensively.

If you need any technical assistance, you can always call the customer support number. In fact, you can also leave your queries below in the comment section – our team will try their best to clear the clouds of confusion.

Let us know how you found this article. We will be looking forward to hearing from you.