Amazon.com : Dog-Thing by Talents10 - Dog Training Prong Collar (Large, 3.5mm Thickness), Metal Collar for Large Dog Obedience Training. Better Than a Choke Chain or Other Dog Collars for Dog Walking :
Rouge Stainless Steel O Ring Eternity Choker Collar – The Feltt
Quikloc Shaft Collar 0-1 inch - QuikLoc All Steel Shaft Collars