Gateron KS-3X1 Milky Switch Review: Budget Linear Performance for Custom Builds

Building a custom mechanical keyboard on a budget often means making compromises on switch quality, sound, or longevity. The Gateron KS-3X1 Milky Switch aims to change that narrative by delivering a smooth, pre-lubed linear experience at a fraction of the cost of premium switches. In this review, we'll put the KS-3X1 through its paces, comparing it to other budget linear switches and evaluating its suitability for both beginners and experienced builders.

Gateron has long been a household name in the mechanical keyboard community, known for producing reliable switches that balance performance and affordability. The KS-3X1 Milky variant—named for its translucent, milky-white housing—is a direct descendant of the popular Gateron Yellow series, but with refined tooling and factory lubrication. Whether you're building your first custom keyboard or looking to stock up on switches for a group build, the KS-3X1 deserves a close look.

Design and Build Quality

The Gateron KS-3X1 Milky Switch features a translucent polycarbonate top housing and a nylon bottom housing, giving it that signature milky appearance. This material combination is known for producing a deeper, fuller sound profile compared to full-polycarbonate switches, while the nylon bottom helps dampen high-pitched clatter. The stem is made from POM (polyoxymethylene), a self-lubricating plastic that contributes to the switch's smoothness over time.

Factory lubrication is applied sparingly but effectively to the slider rails and spring contact points. In our testing, the lune was consistent across a sample of 50 switches, with no noticeable dry spots or over-lubed inconsistencies. The spring is a standard 15mm stainless steel offering a bottom-out force of approximately 55g—similar to the classic Gateron Yellow. The switch housing also features a standard 5-pin design, making it compatible with both PCB-mount and plate-mount builds.

• Top housing: Polycarbonate (milky translucent) | Bottom housing: Nylon | Stem: POM
• Factory lubed on slider rails and spring
• Standard 5-pin layout; compatible with most hot-swap PCBs
• Bottom-out force: ~55g | Total travel: 4.0mm

Typing Experience and Sound Profile

Out of the box, the KS-3X1 Milky Switch feels noticeably smoother than many budget linear switches in its price range. The factory lubrication reduces scratchiness to a minimum, and the POM stem glides effortlessly against the polycarbonate housing. Typing on these switches is a pleasure—each keystroke feels consistent and buttery, with no audible spring ping or wobble. The bottom-out is firm but not harsh, providing a satisfying thock when paired with a well-damped keyboard case.

Sound-wise, the milky housing produces a slightly deeper tone compared to clear or full-polycarbonate Gateron switches. When mounted in a tray-mount board with foam, the KS-3X1 delivers a muted, creamy sound that is pleasant for both office and home use. It's not as loud as clicky switches, but it's also not as silent as heavily dampened linear switches. For those who enjoy a moderate acoustic signature without spending extra on switch films or additional lube, the KS-3X1 is a great starting point.

• Smooth, scratch-free travel thanks to factory lune and POM stem
• Deep, muted sound profile—ideal for quiet environments
• Consistent bottom-out force across all tested switches

Performance in Custom Builds

We tested the Gateron KS-3X1 Milky Switch in three different keyboard configurations: a standard tray-mount plastic case, a gasket-mount aluminum board, and a sandwich-mount acrylic build. In each scenario, the switches performed admirably. The consistent 55g spring weight is light enough for rapid typing sessions but heavy enough to prevent accidental presses during gaming. The short 4mm travel also feels responsive for both productivity and play.

When paired with aftermarket keycaps, the KS-3X1's milky housing diffuses RGB lighting softly, creating a warm, ambient glow rather than a harsh, bright LED look. This makes it an excellent choice for builders who prefer understated aesthetics. For those looking to upgrade their build further, consider adding a set of high-quality keycaps like the Graffiti Party - Cherry Profile Dye-Sub PBT Full Keycap Set or the Lunar Witch - Cherry Profile Dye-Sub PBT Full Keycap Set to complement the switch's smooth feel with a premium typing surface.

• Performs well in tray-mount, gasket-mount, and sandwich-mount builds
• RGB diffusion is warm and even—no hot spots
• Works well with both OEM and Cherry profile keycaps

Comparison to Other Budget Linear Switches

How does the KS-3X1 Milky stack up against competitors like the Cherry MX Red, Kailh Box Red, or the Gateron G Pro 3.0 Switch? The KS-3X1 offers a smoother out-of-the-box experience than the Cherry MX Red, which often requires break-in or additional lubrication. It also edges out the Kailh Box Red in terms of sound depth—the milky housing produces a richer tone compared to the Box Red's higher-pitched clack.

Against the Gateron G Pro 3.0 Switch, the KS-3X1 is slightly more affordable while offering comparable smoothness. The G Pro 3.0 has a slightly lighter spring (50g bottom-out) and a different housing material, but for most users, the difference is marginal. The KS-3X1's main advantage is its price-to-performance ratio: you get 90% of the feel of premium linear switches at nearly half the cost.

• Smoother than Cherry MX Red out of the box
• Deeper sound than Kailh Box Red
• Comparable to Gateron G Pro 3.0 at a lower price point

Who Should Buy the Gateron KS-3X1 Milky Switch?

The KS-3X1 Milky Switch is an excellent choice for budget-conscious builders who want a smooth linear switch without spending a fortune. It's also a great option for newcomers to the custom keyboard hobby who want to experiment with linear switches without committing to expensive options. If you're building a keyboard for a friend or a group buy, the KS-3X1 allows you to equip multiple boards without breaking the bank.

For those who prefer a heavier switch or a more tactile feel, the KS-3X1 may not be the best fit. However, if you enjoy a light-to-medium linear switch with a creamy sound and smooth action, this switch is hard to beat at its price point. Pair it with a quality keyboard like the Keychron Q series or V series for a complete custom experience.

• Ideal for budget custom builds and first-time builders
• Great for office environments where quiet typing is preferred
• Not recommended for users who prefer heavy switches (65g+) or tactile feedback

The Gateron KS-3X1 Milky Switch proves that you don't need to spend a premium to get a premium linear experience. With its smooth factory lubrication, deep sound profile, and consistent performance across multiple build styles, it's a standout choice in the budget switch market. Whether you're upgrading your first mechanical keyboard or stocking up for a custom project, the KS-3X1 delivers exceptional value. To complete your build with a matching aesthetic, consider pairing these switches with the Lunar Witch - Cherry Profile Dye-Sub PBT Full Keycap Set for a cohesive, stylish look that complements the milky housing.