Black nylon deck filler. Finger grip cap with 'O' ring creates an umbreller cover over base to prevent contaminant entering. Security chain to prevent cap falling overboard.
NB: IF AN ITEM IS SOLD AND PAID THROUGH PAYPAL AND THEN CANCELLED YOU WILL BE CHARGED 2.6% + OF TOTAL AS A CANCELLATION FEE THAT WE ARE CHARGED THROUGH PAYPAL