The Pains Wessex Buoysmoke MK9 is a compact Lifebuoy marker which produces dense orange smoke for 15 minutes. Ships are required to carry 2 markers, one mounted on each bridge wing with the brackets supplied and attached by a line to a 4kg lifebuoy. (An approved Lifebuoy Light should also be attached to the lifebuoy).
The signal is used to mark the position of a man overboard in the water during daylight. It can be automatically deployed by releasing the lifebuoy, or manually activated.