Employed by Vets to keep the horses' mouth open whilst treating problems inside the mouth. 

Measures 18 inches overall with a 9 inch gape.

Plus a genuine Rutters Horse Twitch.  Constructed from Beech wood and beautifully turned, thetwo pieces are hinged together.

Again employed by Vets to keep a horse immobile whilst being treated.

The twitch lacks the short fastening strap. Some indication of old worm but not active. Measures 14 inches.

Whilst neither implements are used in modern practice, they are an interesting reminder of bygone days.