SINCE 1916 "Customer's Day": pioneers of public loyalty   This family business, now in its third generation, was started by Basilio Vallejo Abad as manager of the barber shop that the Carralero brothers opened in 1916 on Santa Isabel street, in the Lavapiés neighborhood. In this traditional hairdressing salon, heads and beards were shaved as illustrious as those of the Nobel Prize winner Ramón y Cajal, Jiménez Díaz or Gregorio Marañón, as popular as the by Jose Luis Lopez Vazquez. The tiles on the façade, declared of historical-artistic interest, come from Talavera de la Reina: they represent two haircut scenes, one for a child and the other for an adult, both seated in American-style armchairs, with a metal structure and folding backrest, in contrast to the wooden one that survived in most of the hairdressers of the time. The façade is complemented by the typical hairdressing background in vertical bands that alternate blue, red and white colors and the decoration with panels of rosettes and borders with masks and lyres. Inside the hairdresser's, which looks like a small museum, the traditional American armchairs are still used, the classic cash register, sterilizers, children's chairs, showcases with old colognes and also the utensils of that time: razors , manual razors and hair dryers. The establishment is currently run by Elena and Carlos Vallejo, sons of the previous owner, Pedro Vallejo, and grandsons of the initiator of the saga.