DTS Dual Tube Socket / Chimney Combination for 4CX250 or 4CX350 Series Tubes (Pull) Socket / Chimney Combination has been removed from equipment. Assembly includes 2 sockets with chimneys mounted on a sub-chassis. The socket assembly will work with 4X150 to 4X350, 4CX250 and CX350 series, tubes. NOTE: Will require addition of screen bypass capacitors. No longer available for export.