This set of eight Pratt Sounds, each 11.5" long, are made of 316 surgical stainless steel. Each sound in the series is slightly larger than the one before, and slightly larger on one end than on the other, for a total of 16 sizes.

Pratt sounds are measured in the French scale (also called the French gauge system), which is commonly used to measure the diameter of catheters. It is most often abbreviated as Fr. The French size is three times the diameter in millimeters. A sound of 15 French, for example, would have a diameter of ​5 mm.

Sizes in this set are 13 Fr through 43 Fr.

Safety, Care, and Usage: These instruments should be cleaned and sanitized before and after use. We highly recommend using surgical lube with this product. Use of the Pratt Sounds Set, as with all urethral sounds, is recommended under the guidance of a trained expert.