Treats for sensitive tums?

Since I am moving Alfie on to food for sensitive tums, it makes sense to also consider what treats we give him. Do any of you know of suitable treats? We use Wagg treats at the moment.

Mine don’t have sensitive tums but I have narrowed down the treats based on quality (as I see it). They have a Wainwright’s grain free bone shaped biscuit at bedtime and one of two dried sprats. The bickies come in different flavours so I can vary them. I buy both from Pets at Home. Feelwells do some nice treats and I use their liver and cheese training treats because they are tiny and also don’t make a mess in your pocket.