About the Herm Sprenger Ultra-Plus 2.25mm
Herm Sprenger has manufactured prong collars in Germany for over 100 years and is widely regarded as the standard among professional balanced trainers. The Ultra-Plus is the brand's most-used gauge — a 2.25mm wire collar engineered for small to medium breeds where precision and even pressure distribution matter most.
It's manufactured from high-grade stainless steel with rounded prong tips, precision-cast assembly chain, and the dimensional accuracy that makes the Herm Sprenger range the benchmark for serious training equipment. The base collar weighs under 3oz.
Which breeds and sizes suit the 2.25mm gauge
The Ultra-Plus is designed for dogs between 15 and 40 lb (around 7-18 kg) with necks up to 13 inches (33 cm) in the base size — extendable with additional links for slightly larger necks. Typical breeds include:
- Spaniels: Cocker Spaniel, English Cocker, Cavalier King Charles, smaller Springer Spaniels
- Hound and gun dogs: Beagle, Brittany, smaller Vizsla and Pointer types
- Bulldog types: French Bulldog, Boston Terrier
- Terriers: Jack Russell, Parson Russell, Welsh, Border, Rat, Tibetan Terrier
- Working/utility: Standard Schnauzer (smaller frame), Basenji, smaller Border Collies, smaller Australian Shepherds
- Other: Lurcher and crossbreed types in the 15-40 lb range
If your dog sits at the lower edge (12-15 lb), check whether the 1.5mm Micro-Plus is a better proportional fit. If above 40 lb, step up to the 3.0mm gauge.
Fitting and introducing the collar
Three principles, drawn from the Herm Sprenger usage guide and the consensus of balanced trainers:
- Position high on the neck — behind the ears, just below the jawline. Never low against the shoulder or trachea.
- Two-finger fit — snug enough that the collar stays in place when relaxed, loose enough that two fingers slide flat between the collar and the neck.
- Resize with links, not slack — add or remove individual links so the chain has no looseness when the leash is unweighted. Spare links ship with the collar; replacement links are available individually.
A backup safety connection — a flat collar and back-clip harness, or a slip lead loop — is standard practice. Even a perfectly fitted prong can release if a link works loose; the safety prevents an off-lead moment.
Introduce the collar in a low-stimulus environment first, across two or three short, neutral wear sessions before any leash work, so the collar's presence becomes uneventful.
When not to use the Ultra-Plus
The Ultra-Plus is a training tool, not a permanent walking collar. It should not be used:
- On dogs under approximately 7-9 months of age (breed-dependent)
- For off-leash work, in crates, or during travel
- On dogs with neck, throat, or thyroid conditions without veterinary clearance
- Outside the intended weight class — 15 to 40 lb. Lighter dogs should use the 1.5mm Micro-Plus; heavier dogs the 3.0mm gauge.
If you're new to prong collars, work with an experienced balanced trainer for the first few sessions before progressing to solo handling.
Care and longevity
Stainless steel construction means the Ultra-Plus needs minimal upkeep — rinse and dry after wet-weather sessions, and inspect prong tips every few months for wear. Looked after, a Herm Sprenger collar will outlast almost any other piece of training kit you own. Which is why professional trainers reach for it first.
