a cross - head die for applying a coating layer to a filamentary member , e . g ., plastic insulation to an electrical wire , includes a die body with an axial bore in which a tip holder is removably positioned with tapered surfaces of the holder in engagement with like - tapered surfaces of the bore . the holder is maintained in position by a lock nut on a threaded portion of the holder extending out of the die body . in order to assist in removal of the tip holder , an auxiliary nut , engageable with the threads on the tip holder , is provided . the threads on the collar and lock nut are right - hand , while those on the tip holder and auxiliary nut are left - hand , or vice versa . in order to remove the tip holder , the lock nut is backed off a few turns and the auxiliary nut is threaded on the tip holder until it engages the lock nut . as torque is applied to the auxiliary nut an axial force is exerted on the tip holder , pulling it free of the body bore and permitting its easy removal after both nuts are removed .