PROTO, Industrial Tools

Phone: 800-800-TOOL

Proto® Full Polish Double Box Wrenches - Spline

Features and benefits

  • Proto Spline Tools are designed to service high tensile strength fasteners used widely on military and commercial aircraft and in heavy machinery applications where vibration is prevalent. They are also used in automotive and industrial areas where high performance torque needs to be achieved.
  • Spline fasteners help tighten high strength bolts to high torque loads.
  • They help lower the force required to turn standard fasteners by allowing the torque load to be moved away from the corners, helping prevent fastener rounding. They also turn fasteners with damaged corners.
  • Spline helps reduce foreign object debris (FOD) by having a precise fit between the fastening tool and its fastener.
  • Full polish finish provides corrosion resistance and an easy to clean surface.


Point Size Spline
Unit of Measure Fractional
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ITEM #: Finish Size [in] Outside Head Width 1 [in] Head Thickness 1 [in] Outside Head Width 2 [in] Head Thickness 2 [in] Overall Length [in]
J1118SPL Full Polish 1/4 x 5/16 31/64 1/4 25/64 15/64 7-1/4 Add to Wish list Add to Set
J1122SPL Full Polish 3/8 x 7/16 43/64 11/32 37/64 21/64 8-1/4 Add to Wish list Add to Set
J1126SPL Full Polish 1/2 x 9/16 53/64 3/8 3/4 23/64 9-3/16 Add to Wish list Add to Set
J1130SPL Full Polish 9/16 x 5/8 59/64 13/32 53/64 25/64 9-3/4 Add to Wish list Add to Set
J1135SPL Full Polish 11/16 x 3/4 1-5/64 33/64 63/64 1/2 11 Add to Wish list Add to Set
J1142SPL Full Polish 13/16 x 15/16 1-23/64 37/64 1-5/32 17/32 12-3/4 Add to Wish list Add to Set
J1144SPL Full Polish 7/8 x 1 1-29/64 9/16 1-1/4 35/64 13-1/4 Add to Wish list Add to Set