Start with a Neck Measurement
Before you pick a size, measure your dog's neck where the collar will sit — usually the widest part just behind the ears and jaw. Use a soft measuring tape or a piece of string that you can mark and lay flat against a ruler. Wrap it snug enough that it touches the fur but doesn't press into the skin.
Both the Brain and Thor collars are fully adjustable, but starting with an accurate measurement helps you choose the right size range. The extra small, small, medium, and large options cover most dogs from small breeds to larger ones. If your dog's neck measurement falls near the top of one size, consider going up for a more comfortable fit.
How to Fit the Collar Step by Step
Once you have the collar in hand, the adjustment is straightforward. Follow these steps to get a safe, comfortable fit.
- Unbuckle and loosen the strap: Open the buckle completely and slide the strap adjuster to the loosest setting so you can slip the collar over your dog's head without forcing it.
- Position the collar: Place the collar high on the neck, just behind the ears. The buckle should sit on the side or back, whichever your dog finds more comfortable.
- Tighten to a two-finger fit: Pull the strap until the collar is snug but not tight. You should be able to slide two fingers between the collar and your dog's neck. If you can fit more than two fingers, tighten it a bit.
- Check the D-ring or buckle position: For the Thor collar, make sure the stainless steel D-ring is on top (or at the side you prefer) for leash attachment. For the Brain collar, ensure the 4-point locking buckle is fully engaged and centered.
- Do a final comfort check: Run your hand under the collar to feel for any pinching or twisting. Let your dog wear it for a few minutes indoors before the first walk to see if they adjust well.
What the Adjustable Design Means for Fit
Both the Brain and Thor collars are made from durable polyester that is soft on the fur, which helps reduce rubbing. The adjustment range on each size is generous, so a medium can often fit a dog that is between a small and a medium comfortably. The key is to use the two-finger rule after every adjustment, especially during the first few wears when the collar may settle slightly.
The Thor collar has a sturdy buckle and a stainless steel D-ring for leash attachment. The Brain collar uses a 4-point locking buckle for added security. Both are fully adjustable, so the fit is more about choosing the correct size range than worrying about exact neck circumference down to the millimeter.
Product Facts
- Thor | Collar: The Thor Dog Collar is fully adjustable, super soft on the fur, and made from durable polyester. It has a sturdy buckle and a stainless steel D-ring. The soft polyester and D-ring make it comfortable for daily wear and easy to attach a leash securely.
Thor | Collar - Brain | Collar: The Brain collar is fully adjustable, soft on the fur, and made from durable polyester. Its buckle has a 4-point locking system for added safety. The 4-point locking buckle provides extra security, which is helpful for dogs that pull or are escape artists.
Brain | Collar
What the Catalog Doesn't Tell You About Fit
The catalog confirms that both collars come in four sizes (extra small through large), but it does not list exact neck circumference ranges for each size. This means you should measure your dog's neck and compare it to the size chart on the product page if available, or contact customer support for guidance. The adjustable strap gives you some leeway, but a collar that is too small may not close properly, and one that is too large may tighten unevenly.
Also, the care instructions are not specified in the catalog. For a polyester collar, a gentle hand wash with mild soap and air drying away from direct heat is a safe approach. Avoid machine washing or drying, which can weaken the buckle or D-ring over time.
