Overview Reviews Product Description PARKER HANNIFIN BRASS 640F-6 . (Image is for representation purposes only. Actual product offered may vary). CATEGORY : AUXILIARY FLARE FITTING. Product Videos Custom Field Product Reviews Write a Review Write a Review × Parker Parker 640F-6 Cap Nut For 3/8" Tube Rating * Select Rating 1 star (worst) 2 stars 3 stars (average) 4 stars 5 stars (best) Name Email * Review Subject * Comments *