Cold therapy tools for skin are a fun ritual and a minimal long-term intervention. The temporary vasoconstriction does reduce morning puffiness; the claims about 'reducing pores' or 'tightening' don't survive evidence.
What cold actually does briefly
Constricts surface blood vessels for 30-60 minutes. Reduces under-eye puffiness from fluid pooling. Can soothe acute inflammation (e.g., a flared spot). These effects are temporary and don't accumulate over time.
What cold doesn't do
Shrink pores (the look is brief vasoconstriction; pores don't physically change). Increase 'circulation' to skin in any meaningful long-term way. Replace skincare actives. Provide measurable anti-aging effect.
Use ice rollers for the morning puff fix and the sensory pleasure. Don't expect them to replace the boring work of sunscreen, retinoid, and adequate sleep.