I handmade a shoulder strap for a Thermos vacuum insulated baby straw mug (model number FJL-350). I also have blue, pink, yellow, brown, ivory, and gray colors available, so please check my profile (some may be sold out; I can make them to order if you request a color). *Strap only, mug bottle not included. When you're out with children and have a lot of luggage, a shoulder strap for a straw mug is very convenient for carrying it around. While the official Thermos cover cannot be used as a shoulder strap, this product allows both children and adults to use it as a shoulder strap by adjusting the length of the belt. Attaching and detaching is very easy, just use the Velcro and pass the D-ring through the handle. I didn't want to cover the non-slip bottom, so I made the belt only for the upper part. My grandchild requested that they be able to carry it from the nursery, so I experimented and finally completed it. I use it very conveniently every day. 【Important】Please use it safely, taking care to ensure that the strap does not tighten around the child's neck.