HMX
Hmx Fj400







The FJ400 is one of the HMX Film switches, and among that series it is the one with a medium clack sound. It uses a T series stem, while the P2 bottom housing seen on Cloud switches generates a clacky but full bottom-out sound. Like the Classic and KD200 switches, FJ400 is made using HMX’s newest stem and bottom housing molds, which bring a refined typing feel. Ranked from most to least clacky, the Film switches run KD200, FJ400, 1989. Factory lubed with mixed GPL105 and GPL205 on the leaf spring, stem feet and bottom housing rails.
Last Updated: September 12, 2026
Specifications
Physical Specifications
- Actuation Force
- 50±2g
- Bottom Out Force
- 58g
- Pre-travel
- 2.0mm
- Total Travel
- 3.8±0.2mm
Build & Materials
- Stem Material
- T2
- Factory Lubed
- Yes
- Spring
- 22mm KOS single-stage extended
- Designer
- 80 Retros
Profile Information
- Profile
- Standard Profile
- Type
- Linear
- Silent
- No
- Pin Count
- 5
