Singer Merritt 4525 free arm replacement parts. Plastic knobs set of three for Needle position, needle width and straight/zig zag pattern levers. Should work on Singer models: 4522, 4525, 4526, 4528, 4530, 4538, 6021, 6201, 6202, 6210, 6211, 6212, 6214, 6215, 6217 & 6221 and others. Price includes shipping. Return for refund if fails on your restoration.