I don't know the answer to you question but, why buy 110's when 120's are a more versatile trap that will definitly do the job on rats as well as marten and mink?
Don't have marten here and have caught too many mink to count in 110's
Muskrats are always dead and mink are dead with with the right trigger configuration for the set. I do have 120's but don't have much call for them, although I do use them in my mink boxes in the winter. 110's for me are lighter to carry and pack and do the job.
Used 110's are also very cheap and in abundance. Sure wish I had marten to trap though