Mini Compass & Thermometer for Zipper Pulls (Attach to Jacket or Backpack) (Great Keychain) Go to amazon.com Related posts Top 16 zipper pull thermometer for 2022 FeatureCompass liquid filled for accuracySturdy plastic housingWind chill chart on backAttach to jacket or backpack zipper-pullMakes a nice keychain DescriptionLiquid filled for accuracy. Sturdy plastic housing. Wind chill chart on back.