These are the backplates for the now obsolete and impossible to find Swish overlap fittings.
Fimous 3 Option High Back Rattan Reclining Garden Furniture Set Curved Arm Table
uxcell Aluminum Steering Arm, 3mm for RC Car Double Arm Horn Parts Rod
Cast Iron Fireback Fireplace Fire Back Fire Back Board Back Plate for Fire 2size
Cast Iron Fireback Fireplace Fire Back Rose Fire Back Board Back Plate for Fires
Cast Iron Fireback Plain Fireplace Fire Back Fire Back Board Fire Back Plate
Cast Iron Fireback Fireplace Fire Back Fire Back Board Back Plate for Fires