比如蓝牙要FCC，儿童用品要CPC

1. Manual folding hand fans (paper, bamboo or silk) - cost a couple of pounds or are given away free as event/promotional items, never need charging, batteries or cables, and can be tucked in a pocket or handbag
2. Evaporative cooling towel, damp handkerchief or wet buff wrapped around the neck or wrists - uses free tap water, no electronics, dries and can be re-wetted anywhere
3. Freeze-and-reuse gel neck wrap / ice collar or reusable ice packs taken from the kitchen freezer - one-off low cost, no charging, silent, and doubles for fever or sports-injury use
4. Cooling gel sheets / fever patches or stick-on cooling strips applied to the neck and forehead - cheap, single-use, available in any pharmacy or supermarket and work instantly with no wind or noise
5. Thermal water or facial mist spray can (e.g. pharmacy hydrating mist) - a few pounds, evaporatively cools the face and neck, pocket-sized and re-fillable
6. A plain refillable spray bottle of tap water for DIY face/neck misting - near-zero cost, refillable indefinitely, and can be shared by a whole family
7. Parasol / UV sun umbrella or wide-brim hat with neck flap - removes the direct sunlight that causes the discomfort in the first place, no battery, no maintenance, also provides sun protection
8. Relocating to existing cooled environments instead of carrying a device - shopping centres, libraries, cinemas, cafes, buses, the office or a car with air-conditioning, i.e. 'free-riding' on cooling infrastructure the user already pays for or can access for free
9. Household cooling the user already owns - a desk/standing fan, ceiling fan or air-conditioner used before/after the commute, turning a wearable purchase into a no-purchase decision
10. Switching to lighter moisture-wicking or linen clothing and loosening the collar - costs nothing extra if already owned, eliminates trapped heat that a neck fan is meant to offset
11. Free manual cooling actions - fanning with a newspaper, magazine, folded card or their own hand, or simply taking a cold shower / running cold water over the wrists
12. Consumable cold intake - chilled drinks, iced water bottles, ice lollies or ice cream bought at the corner shop for a fraction of the fan's price, providing perceived relief without any hardware
13. Using a small USB fan they already own plugged into an existing power bank or laptop USB port - reuses hardware already in the home rather than buying a dedicated wearable device

有替代品会影响你的风险