Betsy's Fish consists of two parts; 20% Atlantic Trim of Salmon coupled up with 20% of White Fish (we use Saithe). Fish is a great, easily digestible protein source for dogs and due to the high level of Omega-3 Fatty acids it acts as a natural anti-inflammatory to the body.
Their Beef Tripe is super-stinky and just how we like it. We collect this ourselves from a not-too-local UK site, fresh, and on the day of slaughter, meaning the quality is like no other. 
What else is in this tub of tastiness? We've also got UK Ox Heart, UK Pig Liver and UK Ox Kidney. This may contain some bone within the salmon, but not enough to class as an 80:10:10 so you'll need to couple this up with a bone or balance over a few days.