We've added an option for 1/4" NPT bungs. Little bit more to the point when you're fabbing and air tank for OBA system or something along those lines. Besides, why purchase extra fittings. Weld this one in and install an air line fitting.
http://diy4x.com/cart/index.php?route=product/product&path=39&product_id=198
http://diy4x.com/cart/index.php?route=product/product&path=39&product_id=198
