Compression Fittings - Style 31 Tube Connector - Style 31 Specifications Hose Size ID Part Number ID 'H' Hex Thread Overall Length 'A' 1/4" 160431SKO 0.19" 0.56" 7/16 - 20 1.48" 3/8" 160631SKO 0.30" 0.68" 5/8 - 20 1.78" 1/2" 160831SKO 0.40" 0.88" 3/4 - 20 2.07" 3/4" 381231SKO 0.65" 1.06" 1 - 20 2.50" 1" 381631SKO 0.87" 1.37" 1 1/2 - 20 2.75"