armfloat vs armlet

armfloat

noun
  • An inflatable plastic band, normally worn on the upper arm, to help a wearer float in water and learn to swim. 

armlet

noun
  • A band worn on the arm for ornamental or identification purposes. 

  • A small arm. 

How often have the words armfloat and armlet occurred in a corpus of books? (source: Google Ngram Viewer )