How to choose the right Herman Sprenger prong collar size - a practical guide

The prong collar is one of those tools we get the most questions about, and the first one is almost always the same: "which size should I order?" The good news is that it's not a lottery. The size of a Herman Sprenger prong collar (also called a pinch collar) comes down to two specific parameters you match to your dog: length (the neck circumference) and prong thickness. This guide walks through both, step by step.

A quick word first, in case you're just starting out: Herman Sprenger is a German manufacturer based in Iserlohn, in business since 1876. In IGP/IPO (the protection dog sport), their prong collars are the standard - largely thanks to the quality of the steel and the consistent build. But even the best prong collar only works as it should when it fits well.

Herman Sprenger stainless steel training prong collar with a ClickLock buckle - overview

The two parameters you set

Keep this split in mind, because it runs through the whole guide:

  • Your dog's neck circumference sets the length of the collar - that is, how many links it has.
  • Prong thickness sets how the collar works - how it spreads the pressure.

You match both to your particular dog. Breed alone isn't enough - two dogs of the same breed can need different sizes.

Step 1: measure the neck circumference

This is the basis for choosing the length. You'll need a tailor's tape measure (the soft, fabric kind).

  • Measure snugly - no slack, the tape should sit against the neck.
  • Measure just behind the ears - that's where the collar sits, and the neck is at its narrowest there.
  • The number you write down is the collar length you order.

This matters, because a prong collar only works properly when it sits high, just behind the ears - not slipped down onto the shoulders. Measure at the base of the neck and you'll end up choosing one that's too big.

A Herman Sprenger prong collar fitted high on a dog's neck, just behind the ears
A correctly sized prong collar sits high, just behind the ears.

Step 2: what if your measurement falls between sizes

Prong collars come in standard lengths (for example 41, 52, 58 cm), so your measurement won't always land exactly on one of them. No problem - the length is adjustable:

  • Pick the length closest to your measurement.
  • Add or remove links to reach your exact size.

Spare links are in our range. They just need to match the material and wire thickness of your collar - a link has to fit it, so keep an eye on those two parameters when you order. The swap itself is simple: you slot a link in or take one out, no tools needed. The same principle helps when your dog's neck circumference changes over time - you top up with extra links instead of buying a whole new collar.

Adjusting with links works whatever the prong collar type - semi-slip, ClickLock buckle or Neck-Tech.

Close-up of the ClickLock buckle on a Herman Sprenger prong collar on a dog's neck
The ClickLock buckle - fasten and release in one motion.

Step 3: choose the prong thickness

The second parameter. Sprenger offers four wire thicknesses (the wire the prongs are made from):

  • 2.25 mm - the thinnest
  • 3.0 mm - standard
  • 3.25 mm - standard, the most popular thickness
  • 4.0 mm - the thickest

Here's the rule that often surprises people: the thicker the prong, the gentler it feels. A thicker wire spreads the same pressure more evenly, over a larger area. Thinner prongs feel more intense, because the pressure concentrates on a smaller area.

In practice, thickness is matched to the dog's size and strength:

  • 2.25 mm - small dogs, up to about 20 kg
  • 3.0 mm - standard for medium dogs
  • 3.25 mm - the most popular choice, medium and larger breeds
  • 4.0 mm - large, strong dogs

Bear in mind, though, that weight isn't everything. A dog's working style and temperament matter too, so for borderline cases it's worth talking the choice over with your trainer or with us.

What about the material?

Material is a separate topic - Sprenger prong collars come in stainless steel, a black galvanic coating, Curogan (a nickel-free alloy for dogs with sensitive skin) and chrome-plated steel, among others. Each one gets its own breakdown in a dedicated series on our Instagram and Facebook, with a separate blog article on the subject coming soon.

In summary - an informed choice in three steps

  1. Measure the neck circumference snugly, just behind the ears - that's your length.
  2. Falling between sizes? Take the nearest one and adjust with links.
  3. Choose the prong thickness for your dog's size and character (2.25 to 4.0 mm).

Together, these three steps give you a prong collar matched to one specific dog, rather than one that "more or less fits".

Not sure which length or thickness to choose? Drop us a line - we'll help you match it to your dog.

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