The Divina Proportione series was the last great project of the late Giancarlo Guidi. Giancarlo had a great appreciation for art, as was proven by the expansive Picta series, and for this set of shapes he turned to Franciscan friar, mathematician, and literary translator Luca Bartolomeo de Pacioli for inspiration. Specifically his best-known work, De Divina Proportione, which focused on the application of the Golden Ratio to art and architecture — a text that was illustrated by a particularly noteworthy student of Luca's — one Leonardo da Vinci.

The Ser Jacopo De Divina Proportione is in essence the application of its namesake's teachings applied to the art and architecture of the pipe. Available in a range of finishes, each is accented by a seemingly simple silver accent divided into sections which one could suspect come to around 1:1.618.