Modular glass system
Glass Is Class Gen 2
BTS's house-brand glass system: complete lights, AlphaFit bulbs, housings and pickup kits.
Shop Glass Is Class Gen 2Shop watermelon lights for semi trucks, pickups and custom builds. Explore full-size Glass Is Class Gen 2 and Alpha 360 systems, glass and plastic options, light kits and compact Mini watermelon lights. ...
Choose your style
Featured BTS watermelon-light systems
Three specialty modes
Alpha 360
Explore steady, simulated-rotation and strobe modes, plus matching parts.
For off-road, emergency-display and novelty use only. Not Class 1 or DOT-approved warning equipment.
Shop Alpha 360 lightsBrowse by material or choose a kit
Compact lights. More possibilities.
Mini Watermelon Lights
Get the watermelon look in a compact marker light. Browse Mini styles for big rigs, pickups and custom builds, then check the exact light's dimensions, mounting and wiring.
Mini lights for big rigs
Explore compact watermelon marker-light styles for your truck.
Shop big-rig Mini lights Shown: UPI36214 Double Fury Amber/Red
Mini lights for pickups & custom builds
Explore compact styles for your pickup or custom lighting layout.
Shop pickup & custom Mini lights Shown: UPI34851 Blue/ClearCheck the product's mounting-hole size separately from its outside dimensions, and confirm its wiring and mounting requirements.
Stories & practical guides
Watermelon Light Guides & Stories
The pickup story
How BTS Brought Watermelon Lights to Pickups
The story of Dustin’s one-light F-150 setup, its big-rig roots and the pickup installations that followed.
Read the story
Installation planning
Watermelon Light Mounting & Wiring Guide
Compare mounting holes, attachment methods and wire functions, with part-specific examples and Gen 2 installation checks.
Read the guide
Compare the systems
Alpha 360 vs Glass Is Class Gen 2
Compare the three-mode Alpha 360 lamp with the replaceable AlphaFit Gen 2 system, including mounting, wiring and use restrictions.
Read the guideOther watermelon lights and installation parts
US$20.00
-33%
Original price was: US$15.00.US$10.00Current price is: US$10.00.
Read More
How to choose watermelon lights for your truck
Full-size systems or compact Mini lights?
Start with the look and installation space you want. Full-size watermelon-light ranges include complete lamps, replaceable-component systems and flush-mount kits. Mini watermelon lights offer the same general dome-style look in compact designs, with mounting methods that vary by model. Compare the outside dimensions, required opening and rear clearance separately.
Browse Mini watermelon lights for big rigs or Mini lights for pickups and custom builds. These are shopping routes with some overlapping products; the vehicle label alone does not confirm fitment. The full-size watermelon-light selection guide helps compare larger systems and styles.
Glass or plastic watermelon lights?
Choose the lens appearance you prefer, then compare the exact light. Glass Is Class Gen 2 uses real-glass star lenses with the AlphaFit Gen 2 LED system. Other glass and plastic/polycarbonate lights have their own lens patterns, construction and replacement parts. Lens material alone does not establish brightness, water resistance, service life or mounting compatibility. Glass can chip or break, so follow the handling and installation instructions.
Complete light, replacement part or kit?
A complete assembly, a housing without a bulb, a replacement lens and a kit are different purchases. The Glass Is Class Gen 2 collection includes complete lights and separately sold AlphaFit bulbs, housings and accessories. Check the exact generation and part number when replacing a component.
For a new setup, compare watermelon light kits by their listed contents. A kit may include a lamp, housing, bezel, bracket or wiring, but the combination varies. Check what is already supplied before buying additional hardware.
Lens colour, LED colour and operating modes
Read both the lens colour and the LED output colour. A clear lens may cover an amber, red or other-colour LED. Single-colour, dual-colour and dual-function describe different choices; rotating simulation and strobe are additional product-specific modes. Choose by the exact operating description rather than a colour name alone.
Glass Is Class Gen 2 is the modular glass/AlphaFit route. Alpha 360 is the specialty route for steady, simulated-rotation and strobe modes. BTS lists Alpha 360 for off-road, emergency-display and novelty use only; it is not Class 1 or DOT-approved warning equipment. The Alpha 360 and Glass Is Class Gen 2 comparison explains the differences.
Plan the mounting and wiring before ordering
For a replacement, record the existing part number, mounting dimensions, attachment method, voltage and wire functions. For a new location, measure the opening and space behind it, then check how the light and bracket attach. Interior, mirror, cab and under-truck positions can require different hardware and wiring.
Use the watermelon light mounting and wiring guide for grommet, threaded and glass flush-mount examples. Compare watermelon light brackets against the exact light and mounting location; this collection is a selection resource, not a compatibility list for every Mini or full-size lamp.
FAQ
Watermelon light questions
What are watermelon lights?
Watermelon lights take their name from the rounded, patterned lens style. BTS carries full-size assemblies, compact Mini styles, replacement components and installation kits. Their lighting function, mounting method and electrical requirements depend on the exact product; the shape alone does not establish an approved marker or clearance function.
Does “3/4-inch Mini” describe the lens or the mounting hole?
For United Pacific 34847, 3/4 inch is the mounting-hole diameter; it installs with an included rubber grommet. Other Mini designs differ: United Pacific 36164 Mini Crystal requires a 5/8-inch hole and uses a threaded stud and nut. Use the exact product's outside dimensions and mounting instructions rather than treating “Mini” as one standard size.
Are full-size watermelon lights and replacement parts interchangeable?
Not automatically. Match the part number, generation, lens or housing dimensions, fastening method, voltage and wiring. Two lights with a similar dome can use different bases, brackets and electrical connections. Confirm that a replacement bulb, lens or housing is listed for the exact light you own.
Does a dual-colour watermelon light automatically rotate or strobe?
No. Two LED colours and rotating or strobe modes are different features. Single-colour AlphaFit Gen 2 bulbs have 15W dim and 20W high settings. Dual-colour Glass Is Class AlphaFit bulbs have one power setting; changing colour is different from selecting dim or high. Alpha 360 offers separate steady, simulated-rotation and strobe modes. Follow the instructions for the exact system.
Will a light described for Peterbilt or Kenworth fit every truck from that make?
No. Check the model, year and equipment requirements where listed, then compare the installed opening, mounting points, bracket and wiring. Some lights and brackets are intended for custom installation rather than a factory replacement. A truck make or category name alone is not a complete fitment statement.
Can I install watermelon lights under a pickup truck?
A suitable light and mounting setup can be used for a custom pickup installation. BTS's Glass Is Class Gen 2 pickup-truck watermelon light kit is one route to explore. Check the selected kit's contents, mounting location, clearance and wiring requirements. “Universal” does not mean an OEM bolt-on fit for every year, make and model.
Can every watermelon-light colour be used as a road-going marker light?
No. Check the exact lamp's manufacturer-designated function and the rules for its colour, position and use where the vehicle operates. A decorative or auxiliary colour is not automatically suitable for a required marker or clearance function. Do not use a general colour name or the watermelon shape as evidence of road-use approval.
Is Original Glass Is Class Gen 1 still a current product range?
Original Glass Is Class Gen 1 is discontinued. Its original-generation reference page remains available to help identify older equipment. Glass Is Class Gen 2 is the current system; confirm exact part compatibility rather than assuming that components interchange between generations.