King's Ferro Wiper 30 is the perfect accessory for film development. This tool removes air bubbles between the ferrotype plate and photographic paper. Purchased new about 40 years ago and stored with little use. The black rubber part has some flexibility. No cracks, which is amazing. Practicality is unknown. At the time, I was doing black and white enlargements, so I used it for 4x5 prints. - Brand: King - Product Name: Ferro Wiper - Model: 30 Thank you for viewing.