2This is a small orange-brown bird, 16.5 cm (6.5 in) in length, with a long tail and an undulating flight. The bill is yellow-orange. The male has a grey head and black moustaches (not a beard); the lower tail coverts are also black. The female is generally paler, with no black moustache. Flocks often betray their presence in a reedbed by their characteristic "ping" call.