Abstract: A removable seat for attachment to a support, such as the thwart of a boat, having a mounting housing rotatably secured to the base of the seat. A plurality of support-engaging members are slidably disposed in the housing for removably attaching the seat to the support. Each of the support-engaging members includes a cylindrical bar having an L-shaped end portion to which a rubber disk is attached. Locking means releasably secure each of the support-engaging members to the housing. Each locking means includes a lever which is pivotally attached to the housing and has detent means formed therein for slidably receiving one of the support-engaging members. A resilient means, such as a spring, is disposed between a pair of levers for urging the detent means carried thereby into frictional engagement with the support-engaging member.