Direct Drip 1/4" (250) Tee Barb x Barb x Barb.  A Tee Barbed Fitting can be punched into a 1/2" or 3/4" Solid Drip Hose and will create an outlet for 2 seperate 1/4" drip lines.  Emitters can then be attached to both ends of the 1/4" tubing.