Pickett N4/N4p-ES Slide Rule Twin Pack NIB. Here is a Pickett N4/N4p-ES Slide Rule Twin Pack.The slide rules are made of aluminum and each has 34 scales. The slide rules are unused and still in their original plastic. I haven't removed them from the box. I lifted the inside of the box to take pictures of the manuals. The box is in pretty good condition, showing some signs of storage and age, including discoloration, dings, creases, bumps, etc. Please check my other auctions for more slide rules and related items. Thanks for looking and good luck!