The silicone flat mouthpiece lies flush with the top of the device — it's lower profile, more discreet, and slightly softer on the lips during long sessions. The draw angle is direct rather than angled, which some users prefer. The trade-off: zirconia stays more flavorfully neutral over time and is easier to clean thoroughly. Choose silicone for portability and discretion; choose zirconia for pure flavor transparency.

Minimally and only after extended use. High-quality, heat-cured silicone is food-safe and relatively flavor-neutral, but it absorbs trace residues over time in a way that zirconia doesn't. A thorough ISO clean every 1–2 weeks keeps it performing cleanly. If you notice any off-taste, the mouthpiece is overdue for a clean or replacement.

Yes — the IQ2/IQC Flat Mouthpiece (Silicone) is compatible with both devices. It's one of the few mouthpiece accessories that spans both IQ-series devices in the current lineup.