The Double Peh and Other Letters of Distinction
Comparison of the Doubled Peh from different manuscripts. Source: Baal HaTurim Chumash: The Torah with the Baal HaTurim’s Classic Commentary. Ed. Avie Gold. Mesorah Publications, 2003. p. 1597
Retrieved from: THE MYSTERY OF THE WRAPPED PEI — BY DEVORAH by Deborah Thompson

Then I saw it: a strange letter in the middle of a block of text, in the word HaMishpatim, ‘the laws’. It was a Pei פ (the seventeenth letter of the Aleph Bet) with a large whorl inside its mouth. Of all the unusual letters I’d come across, I had never seen anything like this. The Spiral Pei appeared again a few lines below the first, on a similar word. My heart raced.
Do you see them? The two spiral letters?
I couldn’t comprehend what I was seeing. I had never learned anything about another version of the Pei, and this could have been unique. But something deep in me refused to believe that this was merely a beautiful scribal flourish.
The Baal HaTurim explains that this unusual Pei, which he refers to as the Pei Kefulah (Doubled Pei), teaches us specific lessons each time it appears in the text. This letter represents many things, including themes of delving deeply and doubling. A few examples:

(Devarim 7:12) This Pei Kefulah [on HaMishpatim, ‘these laws’] indicates that it is necessary for a judge to probe and to investigate in order to arrive at the depths of the law. The judge must understand that each testimony is doubled; there are two sides to every story.
(Devarim 15:8) This Pei Kefulah [on phato’ach, ‘open thy hand’] indicates that you who are giving money to another should open, not only your hand, but also your mouth, and speak reassuring words to the recipient (this is a play on words: Peh literally means ‘mouth’). |

In a way, I feel as if the Spiral-Doubled-Pei called out to me personally. It cried out from a torn Torah in a cold museum vitrine where no one else was listening. The mouth of the Pei spoke, saying,
פקוד פקדתי פתח תפתח פנימה
Remember me! Open up and unwrap the meaning within me.
As an artist, scholar, writer, researcher, and daughter of Israel, I feel obliged to delve into the whorls of the Pei Kefulah and deeply understand them—not only for myself—but to share them with others, lest this remarkable letter disappear completely.

Excerpted from: THE MYSTERY OF THE WRAPPED PEI — BY DEVORAH by Deborah Thompson
For a more in depth study please see Teaching Otiot Meshunot by Deborah Thompson