These 3/4 inch stainless 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. They are great for thick-haired breeds with heavy undercoats such as Huskies. It is always best to use the shortest contact point that makes a reliable connection. Warning: As with all contact points, do not leave the collar receiver on the dog for more than 12 hours at a time.