Stem, Air Coolant Adjustment, to fit A-dec 500® Control Block Replacement air coolant stem for 300 & 500 control block (A-dec® #38.0526.00) 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.