Fully concealed and continuously lockable, the WICSTAR opening limiter can be easily controlled via the window handle (one-handed operation) and that can ensure a stepless opening position from 20°up to 90°. The locking of the handle controlled opening limiter is achieved with friction. Additionally, the opening restrictor is equipped with an end stop at 90°, in order to prevent the sash from hitting the window rebate or to prevent damage on the hinges due to over twisting. Typical WICONA: WICSTAR hardware technology works in secret. The handle controlled opening limiter is concealed, nothing disturbs the profile design of the window sash.