Abstract: A device for example for securing a boat to a dock having spaced boards. The device comprises a body having a shaft and an elongated head secured transversely to one end thereof. A plate is mounted on the shaft for slidable movement thereon towards and away from the head with its plane parallel to the head, to provide an adjustable but uniform space between corresponding points on confronting surfaces of the head and the plate. These surfaces, during operation of the device act to grip therebetween planking of the dock. A spring is associated with the shaft and plate to urge the plate towards the head as this space is increased from a minimum value. The device further comprises a ring to which a line from the boat may be secured.