Box-Box Adapters

Connection Length C (mm) Length Shoulder J (mm) Width Spanner flats E (mm) Std bore d (mm) Outside diameter Across Flat F (mm)
Box up A Box down B Top Di (mm) Bottom D2 (mm)
API 2 3/8*REG API 2 3/8*REG 70 20 51 24 78 78 65
API 2 3/8*REG API 2 7/8*REG 152 51 51 25.5 90 90 70
API 2 3/8*REG API 3 1/2*REG 96 35 51 24 114.5 114.5 98.5
API 3 1/2*REG API 3 1/2*REG 178 63.5 51 44.5 114.5 114.5 98.5
API 3 1/2*REG API 4 1/2*REG 92 12.5 70 38 114.5 140 120.5
API 4 1/2*REG API 4 1/2*REG 203 76 51 58.5 146 146 120.5