A device may limit opening of a sash hingedly coupled to a master frame, and includes: a bracket attached to the sash; a first arm having a first end pivotally coupled to the bracket; a second arm having a first end pivotally coupled to the first arm's second end; means for biasing the second arm into a retracted position; and a release assembly. The release assembly is secured to the master frame and includes a hook pivotable between a first position and a second position, which, in the first position, may be releasably received in an opening in the second end of the second arm when the second arm is in the retracted position, as the sash is closed and received within the master window frame The second arm is disengaged from the hook, permitting full opening of the sash, when the hook is pivoted into the second position.

A device may limit opening of a sash hingedly coupled to a master frame, and includes: a bracket attached to the sash; a first arm having a first end pivotally coupled to the bracket; a second arm having a first end pivotally coupled to the first arm's second end; means for biasing the second arm into a retracted position; and a release assembly. The release assembly is secured to the master frame and includes a hook pivotable between a first position and a second position, which, in the first position, may be releasably received in an opening in the second end of the second arm when the second arm is in the retracted position, as the sash is closed and received within the master window frame The second arm is disengaged from the hook, permitting full opening of the sash, when the hook is pivoted into the second position.

A window opening control device for facilitating the secure and adjustable opening of a window. The device features a frame portion having a frame-mount portion for attachment to a window frame and a pivotably attached frame arm, which includes either a pin or a slot. The corresponding sash portion contains a sash-mount portion for attachment to a window sash and a pivotably attached sash arm, which includes the other of the pin or the slot. These components allow for movement between an unlocked position, where the pin is disengaged from the slot, and a locked position, where the pin is secured within the slot. The configuration helps to prevent the window from opening beyond a predetermined distance when the frame and sash arms are locked together, and requires the arms to be unlocked prior to further opening the window.

A window opening control device for facilitating the secure and adjustable opening of a window. The device features a frame portion having a frame-mount portion for attachment to a window frame and a pivotably attached frame arm, which includes either a pin or a slot. The corresponding sash portion contains a sash-mount portion for attachment to a window sash and a pivotably attached sash arm, which includes the other of the pin or the slot. These components allow for movement between an unlocked position, where the pin is disengaged from the slot, and a locked position, where the pin is secured within the slot. The configuration helps to prevent the window from opening beyond a predetermined distance when the frame and sash arms are locked together, and requires the arms to be unlocked prior to further opening the window.