This work was included in Bridget Riley's first major retrospective, staged by the Arts Council at the Hayward Gallery in 1971.

It dates from one of the most experimental moments in Riley's early career. Following the success of her black and white paintings of the 1960s, Riley began to introduce greys and then colours into her work. The present work typifies a number of such studies in which Riley explores the proximity of one colour to the next, the effects of changing the widths of the colour and the impact of entwining colours. Related works were also included in her exhibition at Beyeler Gallery a couple of years later.