1
general::
Phrase(s): fit like a glove
Fig. to fit very well; to fit snugly. • My new shoes fit like a glove. • My new coat is a little tight. It fits like a glove.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Be the right size and well suited; also, be in conformity with. For example, That position fits him like a glove. Tobias Smollett used this simile, rather incongruously, in Humphry Clinker (1771): "The boots . . . fitted me like a glove." [Second half of 1700s] Also see TO A T.
American Heritage Idioms