Check the listing for details. USED-Herm Sprenger Chrome Plated Ultra Plus Dog Prong Training Collar 25"x4mm. Condition: Used. Listed at 35.00 USD. PRODUCT INFORMATION: Herm Sprenger Chrome Plated Steel Prong Collar: This Herm Sprenger prong collar is designed for dogs with NECK SIZE UP TO 21 inches (53 cm); Overall collar length is 25 inches (63 cm); Wire gauge is 4.0 mmCollar Characteristics: Martingale-style Ultra-Plus training prong dog collar with center plate and assembly chain; This professional training dog collar is made of chrome plated steel and has two O rings for connection with the leashUse and Functionality: Safe dog training tool when used properly and under supervision; Blunt ends of the collar will not scratch dog’s skin; Center plate positions links in a way to allow application of even pressure to the dog’s neckRemovable Links: Slightly beveled prongs; Interlocking links, each link equipped with two blunt prongs; Links can be added to make the collar longer or removed to make it shorter; Up to 4 links can be added or removedMade in Germany: With precise German engineering, reliability, and quality by the world's foremost manufacturer of top-quality training collars; HS-Germany INOX-stamp on all rings, as well as center and fastener plates