This Effé is an Ito-ya exclusive design created in collaboration with Plus Jack. The Effé is a rescue whistle accessory that combines "everyday" and "what if" scenarios. It is made by Plus Jack, an eyewear workshop in Sabae City, Fukui Prefecture. It was created with the desire to be "like a lucky charm" that can be worn as an accessory in everyday life and protect the wearer in times of need. It is designed to emit a high frequency range (4 kHz) that is said to be easily heard even from under rubble, within the human audible frequency range (2 kHz to 5 kHz). It is also designed to have a clean frequency peak, including the frequency range of 20 kHz and above that rescue dogs can hear. The sound volume is an average of 85 dB or more for 5 seconds, loud enough to be heard from a distance. (Measured under the guidance of the Fukui Prefectural Industrial Technology Center. Generally, a sound volume of 60 dB or more is said to be loud enough for people to perceive as loud.) The mouthpiece is sized and structured so that even people with low lung capacity or small children can easily produce a sound. The material is Italian cellulose acetate, which is used in eyeglass frames. In Italian, "F" is pronounced "effe." This "F" has various meanings, as seen in words like FUKUI (Fukui Prefecture), FACTORY (factory), and FUE (flute).
