Designed for high-drive, more stubborn dogs by offering a higher static stimulation range than the SD-425X. Choose to train with vibration (buzz), tone (beep), or 21 levels of static simulation in either momentary (nick) or continuous. Waterproof and submersible to 25 feet using DryTek technology. Lithium ion, rechargeable batteries feature a 2-hour quick charge, and a low battery indicator lets you know when to charge. Fits dogs 8 pounds or larger with neck sizes 5" - 22".The SportDOG Brand FieldTrainer 425XS is our smallest and lightest e-collar built for in-the-field training or hunting with close working dogs. This'S' model (SD-425XS) was built for high-drive, more stubborn dogs by offering a higher static stimulation range than the 425X. Consistency and perfect timing are critical to developing your sporting dog, so the remote is quickly and easily operated without having to look at it - which lets you focus on your dog and not your equipment. With only a slight movement of the dial and the push of a button, you will be able to deliver a tone, vibration, or one of the 21 levels of static stimulation. The display of this Authorized Retailer Logo indicates that this independent merchant has been recognized by Radio Systems Corporation ("RSC") as an Authorized Retailer of RSC retail products. Authorized Retailers are not agents of RSC or otherwise affilliated with RSC.