Gazzew Boba U4 (Silent Tactile) $5.50 / 10

The Gazzew Boba U4 is what you reach for when you need tactile feedback but cannot afford to disturb everyone around you. Built on the same Nylon housing as its louder sibling the U4T, the U4 swaps the POM stem for a UHMWPE (Ultra High Molecular Weight Polyethylene) stem with integrated silicone dampeners on both the upstroke and downstroke. The result is a switch that gives you a clear tactile bump with virtually no audible sound on the bottom or top of travel.

The tactile bump on the U4 is slightly less pronounced than the U4T — it is still a meaningful tactile, not a ghost of one — but the UHMWPE stem does introduce a subtly different texture to the keypress. UHMWPE is an extremely low-friction material, which means the U4 feels silky from top to bottom, with the tactile event arriving cleanly in the middle of the downstroke.

Sound profile is best described as a quiet thud. You will hear something — no mechanical switch is truly silent — but in an office or near a sleeping partner, the U4 is dramatically quieter than any unsilenced tactile or linear. The dampening is effective without the mushy quality that plagues some silent switches.

Lubing the U4 requires caution. The silicone dampeners are pre-positioned on the stem and should not be soaked in lube. A light application of 3203 or Tribosys 3204 on the rails works well. The spring can receive a thin coat of 105 oil to eliminate any ping. Avoid 205g0 on the stem itself — it may interfere with the dampeners over time.

The U4 is ideal for remote workers on video calls, office keyboard users, students in libraries, or anyone who wants the typing satisfaction of a pronounced tactile without making enemies. It pairs best with boards that have some dampening material already, like PE foam or case foam, which further reduces any remaining sound. At the same price as the U4T, the choice between them comes down entirely to your environment.