Wilson-Garner regularly manufactures Test Bolts and stocks Test Nuts and Test Washers suitable for torque-tension testing based on John Deere’s Engineering Standard JDM F15. Per the spec, our parts conform to ISO 16047 and ISO 4014. Test products need to be uniform from test to test, so we hold ourselves to exacting quality standards to ensure that you get consistent testing results time after time. In addition, based on customer feedback, we re-roll the threads on all of our test bolts after heat treat and surface finish to eliminate nicks or plating inconsistencies.. You can look at the charts below to see part number requirements for JDM F15. You can click on the part numbers for more information, or click here to request a quote.