As part of a collaboration between Perfume and Isetan Shinjuku, the "Perfume Dance Heels" high heels, designed by the members of Perfume, have been released. The members are also wearing these heels in the dance scenes in their new music video. Based on the members' feedback, these heels were released under Mitsukoshi Isetan's private brand, "NUMBER TWENTY-ONE," as the perfect high heels for dancing. These simple round-toe high heels are available in three colors: gold (metallic), which the members wear in the music video for their new song "Pick Me Up," released on April 29, as well as black (suede), and white (suede). Sizes range from 22cm to 25cm. They are available in the women's shoe section on the second floor of the store's main building. During product development, the members repeatedly tried on prototypes and made repeated revisions. To enhance ease of dancing, the soles are fitted with Vibram soles. The insoles also feature a slightly brushed texture to prevent slipping, and the words "Perfume x ISETAN" are embossed on the inside. According to a product development representative, "Although it's not an obvious detail, the members raised concerns about whether the heel of the high heel would stay firmly in place when landing. We made repeated prototypes to improve stability, and after making adjustments to ensure the center of the heel was aligned with the center of the heel, we finally created a product that was ready for sale." Number Twenty-One is a private shoe brand from Isetan Mitsukoshi, named after the 21st Grimm fairy tale, "Cinderella." The brand offers shoes that combine functionality and design.