Fix three Slotted Plates to the back of the frame and insert three T-screws into matching positions in the wall.
Bag contains 3 slotted plates 6 screws, 3 T-screws and 3 fat wall plugs.
T-Screw Kits for Wood & Polymer Frames
T-Screw is turned with a T-screw spanner which slips behind the frame. When turned it locks into the slotted plate on a wooden frame or into the channel of an aluminium frame. Can then only be released with a similar spanner.
This hidden fixing makes the frame safe and secure on the wall. No ugly picture plates sticking out from either side.