Patent ID: 8151540

Claim:
Method of increasing the impact or impulse resistance of a window pane, comprising, a) providing an anchoring device comprising first and second engagement members; b) directly attaching said second engagement member to a selected window frame portion; c) adhering a window film to a window pane inner surface having a first visible portion dimension and a second visible portion dimension such that a free film portion not adhering to said pane extends from the visible pane portion; d) positioning said free film portion to be in close proximity to said second engagement member; and e) interlocking said first engagement member with said second engagement member such that said free film portion is being constantly pressed by said first and second engagement members and said free film portion terminates in a distal direction of the first engagement member in respect to the window pane; f) attaching said first engagement member to the selected frame portion, whereby film engaging surfaces of said first engagement member are in lateral motion preventing relation with complementary film engaging surfaces of said second engagement member.