Q.D. Barb, 1/4, Vinyl HP Tubing, to fit A-dec 300® and 500® Control Block (A-dec® #023.088.00) For A-dec 500® & 300® Series A-dec®, A-dec 500® and A-dec 300® are a registered trademark of A-dec, Inc. DCI has no affiliation with A-dec and A-dec has not authorized DCI replacement parts to be used on or in connection with A-dec® products.