Herm SprengerProng Dog Collar – Stainless Steel Training Collar with Quick Release ClicLock Buckle, 3 Extra Links, 30 Comfort Tips, for Small Medium Large Dogs, Made in Germany

This worked amazingly well. I am now able to walk my powerful medium size dog with zero issues. The additional links are easy to install, and I used a couple of the little rubber caps on the front of the collar where her windpipe is to be safe. Zero issues, she let's me put it on because walk time is her favorite time. She pulled once, and that fixed the problem. I get to walk down the street now without her gagging and trying to yank my arm off. It literally stopped the pulling the first time I put it on her.

Once I educated myself on how to use the prong it has been a heaven sent experience for me and my Rottweiler/Doberman rescue. No more pulling, we communicate effectively and clearly with each other.

This is the right one but the quick release is not worthy. It is easy enough to open/close by pressing one prong from the sides.This is the 2.24 mm version

I have been using a no brand prong collar for my gsd for almost 2 years, and it started to discolour and rust a while ago. So now i bought stainless steel HS, with hope that it will last forever. This is original HS collar from authorized amazon seller. For my gsd's 45cm (17,7 inch) neck, i only added 1 extra link, and 'shorten' the chain with a cable tie, so it will fit better. For dogs that pull, i highly recommend this collar as it's a real game changer. Just make sure to learn how to use it properly, and this will make your dog walking - or in my case, dog biking - so much easier and enjoyable. The quick realease buckle also makes things easier.