Comparison : Item # 1317-36-168, M6 x 1.0 MPT Metric Straight Ball Check Grease Fitting Steel
Item # 1317-36-174, M8 x 1.0 MPT Metric Straight Ball Check Grease Fitting Steel
Item # 1317-36-180, M10 x 1.0 MPT Metric Straight Ball Check Grease Fitting Steel