BARROW's new thread spacer allows you to make micro adjustments by shortening the length of the exposed male G1/4" thread on any fitting with thread length long enough to accommodate it. Spacer is 1.5 mm thick, so a fitting with 5mm of exposed male thread can be shortened to only 3.5 mm while still providing a good seal utilizing the spacer's integrated o-ring on one side. Made of Brass and with an outer diameter made to match up cleanly with most fittings.