Palatal expansion screw with anatomically bent retention arms that can be easily soldered or welded to molar bands. The specially designed housing fits the palatal vault perfectly. An integrated Polyamid-Insert Nut prevents the screw from backing up. Laser marking for Torsional direction and expansion on housing. Vector 600 Expansion 11mm, 10.4B x 4.0H x 15L 1/10 Pieces