Section Valve Number Description Outer Diameter Inner Diameter Connection View File
1 G221B  7 3/8" OD G-Low Torque Lower Top Drive for National Type Top Drive  7.375  1.875  HT-50 G221B100
2 GM58B  Dual Ball Valve for Maritime Hydraulic Type Top Drive w/ 2 1/8" Stem  7.750  2.750  6 5/8 Reg. GM58B100
3 G305  6 5/8" OD Dual Crank G-Low Torque Upper Top Drive Valve  6.625  2.250  3 1/2 IF G305-100
3 G305B  6 5/8" OD Dual Crank G-Low Torque Upper Top Drive Valve  6.625  2.250  3 1/2 IF G305B100
4 G350B  7 3/8" OD G-Low Torque Lower Top Drive Valve  7.375  3.062  5 1/2 FH G350B100
5 G381B  5 3/8" OD Dual Ball G-Low Torque Upper Top Drive Valve  5.375  2.250  3 1/2 IF G381B100
6 G380B  6 15/16" OD Dual Ball G-Low Torque Upper Top Drive Valve  6.938  2.750  4 1/2 IF G380B100
7 G475B  6 15/16" OD Dual Ball Top Drive Valve w/ 4 1/4 Internals  6.938  2.750  4 1/2 IF Box G475B100
8 G476B  7 3/4" OD Dual Ball Top Drive Valve w/ 4 1/4 Internals   7.750  2.750  6 5/8 Reg. Box G476B100
9 G330B  9 1/2 OD Dual Crank G-Low Torque Valve for National Top Drive  9.480  4.000

 6 5/8 IF Box

 7 5/8 Reg. w/ SRG Pin

 G330B100
10 G586  10" OD Dual Crank G-Low Torque Top Drive Valve  10.000  4.000

 8 5/8 Reg. w/ SRG Pin

 8 5/8 Reg. Box

 G586-100
11 G434B  7 3/8" OD G-Low Torque Lower Valve for National Top Drive  7.375  3.062  4 1/2 IF G434B100