These 5/8-inch Titanium contact points fit all Educator brand training collar receivers. Only fits Educator Brand models 300,400,800, 1200, EZ Educator, Pro Educator and BP-504 Barkless Collar, BP-504-C No Bark Collar and 1000 E-Fence. Many contact points are manufactured with a stainless steel material that contains nickel which often causes reddening of the skin at the point of contact in sensitive dogs. These Titanium contact points are made without nickel, enabling your dog to wear the collar without experiencing redness and irritation. Contact points are available in a wide range of sizes and selecting the shortest contact point that makes a reliable connection is recommended. The 5/8-inch size is recommended for short to medium haired breeds such as Australian Terriers, Hounds, Beagles, Border Collies, Coonhounds, Chihuahuas, Doberman Pinschers, Havanese, Mastiffs, Pugs, Rottweilers, Schnauzers, American Staffordshire, Wire Fox Terriers and many more.