Piper is a pit-bull hybrid (a nice way of saying he’s a mixed up Pit with taller legs than his true Pit cousins!) with a girth measurement of 29 inches and a neck to tail base length of about 21 inches. The medium Approach is a good fit for him and allows him to carry all the food he needs for a 7 night outing. This pack sits stable on him and doesn't slide no matter what Piper puts it through. I would buy this pack again.

i have a 60# black lab mix, realy he is a heinz 57(alittle bit of everything). he uses the med. size pack and it works great. enough room to pack a weeks worth of food easy. seems to be comfy for the dog and you can adjust as you need to with the chest and belly straps. would buy it again if ever needed.

Okay really I got the Approach 2 pack, and it's not on here anymore, but it's still a good pack. Easy to keep clean, easy to adjust, looks good! I have a belgian malinois ( google it if you don't know what it is, and NO it's not a german shepherd.) and if I had gone by the sizing I would have gotton a Large, but my dog is a medium. But returning something through these guys is easy, so if you need to adjust it's cool. I was a bit of a turd and went to a local store that sold the same item I bought to make sure I was getting the right size, and ordered it from these guys! It was the first thing I had got from here, and it won't be the last. Ruffwear makes good durable stuff anyway, my dog doen't mind wearing it. Keep in mind that you should only put 1/3 of your dogs weight into the saddle bags no mater how much your dog weighs. The medium for my dog is a good fit with out sliping. Had I gone with a large I wouldn't have been able to adjust it right and the back strap was right under his doggie junk, so if he peed I would have to wash it. The back strap should NOT ride right under the doggie junk, cause chaffing is bad, person or dog.

My 60 pound Alaskan Husky fits this pack very well. The adjustable straps make for a semi-custom fit. The pack balances very well even while the dog runs. If you want a pack, this is the one.

My dog loves hiking, and throwing her backpack on gives her a great job on the trail. On overnight trips, the pack caries her food, dish and water, and on day trips, she caries our beer! Also doubles as a dog luggage bag for weekend trips out to friends places.

This is the first dog pack I have had. I researched a lot of them and always came back to the Ruffwear. The sternum and chest strap was perfect for keeping the pack straight on my pall. She ran, jumped, tore through the under brush and was chest deep in snow. The pack did not slip or cause hot or rub spots. It appeared very comfortable for her to wear and it was easy to access the compartments. It was very easy to set up and adjust the straps to fit appropriately.

Between the size M Webmaster Harness first strap (that goes around dog's chest) and the size M Approach Pack first strap, the Approach strap is TWO INCHES SHORTER. They are both described as 'performance fit'. So this pack would have fit if Ruffwear kept the dimensions the same - their size M says they are the same, but not so.

I bought the M (26in-36in) since my dog's girth is 31in and it does NOT in any way fit him! It is a good 4in too short around the widest part of his ribcage so I can't fasten it into place. The second fastener near the rear of his body closes just fine. I have the web harness size M and that fits him fine, he is a boxer/ridgeback mix, 70lbs., so the M should have fit him. Ruffwear's site suggests sizing down if in between sizes, but I would size UP. The tag says, 'performance fit' so maybe that explains the difference. The quality of this pack otherwise looks great and I own a lot of Ruffwear products but I have to give a low rating for the misinformation and inconvenience. Here's hoping the L works...