Calligraphers use pens with various widths of nibs. As these pens are not sold in the market, the calligraphers themselves produce by scraping bamboos or reeds.
Istanbul mosques with calligraphy and letter Vav
Arabic Calligraphy: Silence | صمت
Tsumago-juku, Nagano, Japan
Beautiful Islamic Calligraphy Art
Islamic calligraphy. Timeless.