Each column has white dots on it which is used to count numbers. The counting frame can be used as a knitting row counter or to add sums of money. A black rectangle with four plastic movable columns"Brynolf pocket counter made for Royal National Institute for the Blind by Peter Tilling Plastics Ltd" on front of counter. "Royal National Institute for the Blind Brynolf Pocket Counter Catalogue No. 9484" on box.assistive devices, peter tilling plastics