A safety device is presented for securely stowing a double sharp-ended needle. The device comprises a tubular adapter with a longitudinally-elongated channel. A needle holder is located in the channel to move from a distal orientation, in which one needle end projects from a distal adapter opening, and a proximal orientation, in which both needle ends are enclosed within the adapter body. A top plate transitions from a distal orientation, in which the plate is distal from a proximal adapter opening, and a proximal orientation, in which the top plate obstructs the proximal adapter opening. An actuator plate is attached to the adapter body to transition from a first position where the actuator plate retains the needle holder and top plate in distal orientations, and a second position where the needle holder and top plate move to proximal orientations.