Included are multiple camera claws of a second mount that are insertable between multiple accessory claws, and that are capable of coupling by bayonet coupling, multiple contact pins disposed following the circumferential direction of a mount, and a biasing unit to bias the multiple accessory claws in a direction parallel to a center axis of the second mount. The second mount can be relatively rotated to a first state where the accessory claws are inserted between the camera claws, and a second state where the camera claws engage with the accessory claws in the direction. The biasing unit biases a first accessory claw in the direction in the second state, and a first contact pin included in multiple camera-side contact pins situated at the nearest side of the mounting direction of an accessory overlaps the biasing unit in the radial direction.