What Size Greenies To Feed My Dog?

[nadz]

i feed my mini dachshund greenies every now and then, usually after a bath (to clean his teeth haha!). He is just under 4kgs. I gave him the regular size today ($5 one) and he couldnt finish it, too much for him. They are available 2 sizes smaller, but these are quite small and look like they could cause choking. Should i go with the smaller size or stick with regular? I supervise when he chews them!

Otherwise, are there other brands which are better for cleaning teeth? He gets RMBs almost daily but i like something he can chew inside every now and then

Thanks!