The 48-prong naka-araho is for tea ceremony practitioners who are at a level where they can whisk matcha despite the smaller number of prongs (or belong to a school that uses this type of prong).
This chasen comes from master craftsman Tango Tanimura's Wahokudo Studio in Takayama, Nara, Japan.
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The "Number" represents the approximate but not exact number of prongs, and the more prongs, the more froth or foam it produces. However, this is not an indication of better quality as some schools of tea ceremony frown upon froth. The biggest school of tea ceremony, Urasenke, teaches that an even level of froth is desirable, and so this has become standard among non-practitioners.
||常穂・並穂 Joho or Namiho
||数穂・繁穂 Kazuho or Binho
||八十本立 (No special name, characters mean "80-prong")
||百本立 (No special name, characters mean "100-prong")
||百二十本立 (No special name, characters mean "120-prong")
NAME: Matcha Bamboo Whisk 48
DIAMETER (bottom): 2.2 cm (0.87 in)
HEIGHT: 11 cm (4.33 in)
Measurements above are approximate
NOTE: Color may not be exactly as photographed.
ORIGIN: Made in Japan