The components of activator are all except:

COMPONENTS OF THE ACTIVATOR It consists of the following elements: Labial bow: The wire used is spring hardened 0.9 mm stainless steel. The primary wire element of the activator consists of an upper and/or lower labial bow. It consist of horizontal middle sections, two vertical loops and wire extensions through the canine-deciduous first molar embrasure into the acrylic body. Jack screw:  Optional (fitted to maxillary arch). Acrylic portion: This can be fabricated in cold cure acrylic directly on the models or a wax matrix can be made first and then invested in the flask. Key Concept:  Delta Clasp is used in Twin Block appliance. Reference: Textbook of orthodontics 2nd ed Gurkeerat Singh page no 519