These are nice electrode pads that are durable and flexible and are excellent for applying around joints such as wrists or elbows. These pads can be used for areas of the body that are flat, like back or thighs. They are great quality and come with a thick layer of non-irritating conductive gel that adheres well to your skin, but leaves no sticky residue when the electrodes are removed. Electrodes are Reusable They wipe clean with a damp cloth. The Measurements are: 3" (7.5 cm) by 1.77" (4.5 cm). Pin diameter is 3.5 mm. Includes 40 Pads (20 sets). Each set (2 pads) is packaged in a resealable storage bag. **AS AN ADDED BONUS*** => A SET OF 2 SMALL OVAL ELECTRODES WILL BE INCLUDED WITH YOUR ORDER! :) These high-quality pads are compatible with many brand name Digital Massagers with leads that connect to 3.5 snap pads. Feel free to message me through eCRATER Messaging if you have questions on compatibility. Thank you and have a wonderful day!