These leather strings (buffalo and deer) are my cat's absolute favorite toys of all time. The deer one, being kind of lighter in weight and shorter, is her go-to for dragging around on her own. I see her with it several times a day, and she leaves it in her favorite spots in the house. The buffalo one is thicker/sturdier and has more length--she loves for me to use as her primary "interactive" toy (i.e. I drag it across the floor like prey and she goes nuts!). Really a great purchase.