These are the 70's triangle cut Halter Tops that will fit most body types. Please measure yourself to make sure these items will work out the way you are hoping.
Yes, you can teach your rattie to walk on a leash. Make sure that the harness fits the rattie properly and use a short leash to start. Train the rattie inside just in case the rattie would "slip the harness". Never, I repeat, never use a collar on a rattie. For a collar to be tight enough for a rattie not to get out of... it would do serious harm to the rattie, if not kill it.
In the high plains of South Dakota, USA