Set of 6 vintage nesting ashtrays

Nesting ashtrays. Based on an original brass drawing by Walter Bosse, this ceramic ashtray was used by the Russian airline Aeroflot as a souvenir gift in the late 1950s. The concave sea urchin-shaped containers nest into each other others from largest to smallest, forming a complete hedgehog figure when fully stacked. The lower piece is missing (see photos) the rest is intact. 6 pieces. Hooked on the biggest. Length of the largest 15 cm. Length of the smallest 8 cm.