An ornate saddle, whos leather is embosed with the design of various animals, which are all running in the same direction.

Perfect Fit: You can, as a bonus action, resize this item so that it fits any beast of size large or below. 

Easy, Partner: You can, as an action, try to equip a non-hostile beast of size large or below , that is within 5 feet of you, with this item. Make a DC 15 animal handling check and ,on a success, the beast is equiped with this item. On a fail the beast is not equiped  with this item and it becomes hostile towards you.

Giddy up: You can, as an action, mount or dismount , any beast, that is equiped with this item. Your walking speed becomes equal to the walking speed of the beast for as long as you are riding the beast .

Yee-haw:While riding a beast , you can, as a bonus action, utter the command phrase, which is a long YEEEEEE-HAW. If you do, you can, until the end of your turn, occupy the same space as an enemy and your movement  during that turn doesn't provoke opportunity attacks.

An enemy, that shares a space with you for the first time during that turn, must make a DC 15 Dexterity saving throw. On a fail, they  take 2d6 bludgeonig damage and are knocked prone. On a success, they  take half as much bludgeonig damage and aren't knocked prone .

You can use this feature a number of times equal to your animal handling ability modifier and regain all uses after a  long rest.

Notes: ranger