WSP frames also known as three quarter frames.
Made from New Zealand Radiata Pine Timber.
Wire:stainless spring steel AISI304, dia: 0.375.
Eyelets: 2.5mm diameter and 4.5-mm long.
Frames are stapled with 19-22 mm staple pins, 3 staples on each side of top bar and 2 staple pins on each side of bottom bar. 10 pins per frame.