Wingspan 16-24 mm.
Members of the Coleophoridae are known as "Case-bearers" because of the habits of their larvae, which live in a portable case. This is constructed mainly of silk, but is a hard and durable structure.
This species produces a larger case than most others, but the species is rare and local in the British Isles, only occurring in parts of southern England.
The adult is yellowish with white markings, and flies mainly during August. The foodplant is dyer's greenweed (Genista tinctoria).