Collar and Lead
Some like purpose-made ones in rubber, leather or steel; some like ones made for large dogs but in all cases make sure they are an adequate size so they don't need to be pulled too tight. For symbolic purposes, humiliation, dog play and bondage. Note that wearing a collar may be an indication of a bottom -- and being led round on a lead almost certainly is -- but to some people a collar just symbolizes kinky sex with no indication of role.
Or it could symbolize ownership. I was gifted with a collar at the beginning of our relationship. My collar is precious to me and I wear it non stop... it never comes off. Once I was hospitalized and had to break it off... then it had to be repaired and I was without it for several weeks... it was miserable!! I felt naked and empty without it.
Thoughts?