Reference
Glossary
Plain-language definitions of the terms we use across our reviews — so you (and the AI assistants that cite us) get them right.
- Active Noise Cancellation (ANC)
- A technology in headphones and earbuds that uses microphones to detect ambient sound and plays an inverted sound wave to cancel it, reducing steady noise like HVAC, engines, and fans.
- Microcurrent
- A low-level electrical current used in at-home skincare devices to stimulate facial muscles, producing a short-term lifting and toning effect that fades over days without repeated use.
- Red Light Therapy (LED)
- The use of specific red and near-infrared light wavelengths from an LED device to target skin, with clinical evidence for gradual improvements in texture and tone over weeks of consistent use.
- LiFePO4 (Lithium Iron Phosphate)
- A lithium battery chemistry used in modern portable power stations, valued for long cycle life (typically 3,000–4,000+ cycles) and better thermal stability than older lithium-ion cells.
- Watt-hour (Wh)
- A unit of energy capacity. For a power station, usable watt-hours — the energy you can actually draw — typically run 10–15% below the rated figure due to conversion losses.
- Heart Rate Variability (HRV)
- The variation in time between heartbeats, measured by smart rings and watches as a signal of recovery and stress. Higher HRV generally indicates better recovery.
- Sleep Staging
- A wearable's estimate of how long you spent in light, deep, and REM sleep. Accuracy varies by device; finger-worn sensors (smart rings) tend to track it more reliably than wrist trackers.
- Bluetooth Multipoint
- A feature that lets headphones or earbuds stay connected to two devices at once — for example a laptop and a phone — and switch audio between them automatically.
- Pure Sine Wave
- A clean AC power output (matching grid electricity) provided by quality power stations, required to safely run sensitive electronics like laptops, CPAP machines, and medical devices.
- Pressure Sensor (toothbrush)
- A sensor in an electric toothbrush that warns you — visually or with haptics — when you brush too hard, the single most useful feature for preventing gum recession.