None screw hole designs, beautiful and stable. Make of nylon materials, strong and Enduring, not easily deformed. Suitable for frame connection, a 6mm/0.24inch diameter locking hole is required for the vertical panel, and the thickness of plate should be greater than 16mm/0.63inch. Most of it is connecting at a 90 degree right angles, but can also be connecting at a 45 degree obliquely angles. When connecting at other angles, plate thickness should be greater than 18mm/0.71inch. Suitable for use with panel furniture, Unable to see screw holes after installation. It is generally used for connecting outer frame, especially suitable for connecting open cabinet frame, such as antique shelves, bookshelves, open shelves, display cabinets.