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Castle Nuts

224 Results Found that Include 224 Products

Results per page:  16 | 32 | 48
Carbon Steel Castle Nut with 1-1/4"-7 Dia./Thread
Steel Castle Nut with 1-3/8"-12 Dia./Thread Size
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Steel Castle Nut with 1-3/8"-12 Dia./Thread Size and Plain Finish; PK5 Steel Castle Nut with 1-3/8"-12 Dia./Thread Size and Plain Finish; PK5
  • Item # 6YHL2
  • Mfr. Model # 371445G
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Steel, Material Grade Grade 5, Fastener Finish Plain,...More

Steel Castle Nut with 1/2"-13 Dia./Thread Size an
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Steel Castle Nut with 1/2"-13 Dia./Thread Size and Plain Finish; PK5 Steel Castle Nut with 1/2"-13 Dia./Thread Size and Plain Finish; PK5
  • Item # 41UA06
  • Mfr. Model # U12040.050.0001
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Steel, Material Grade Grade 2H, Fastener Finish...More

Low Carbon Steel Castle Nut with 1/2"-13 Dia./Thr
Low Carbon Steel Castle Nut with 5/8"-11 Dia./Thr
Steel Castle Nut with 1"-14 Dia./Thread Size and
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Steel Castle Nut with 1"-14 Dia./Thread Size and Plain Finish; PK5 Steel Castle Nut with 1"-14 Dia./Thread Size and Plain Finish; PK5
  • Item # 6YRL7
  • Mfr. Model # 354315G
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Steel, Material Grade Grade 5, Fastener Finish Plain,...More

Low Carbon Steel Castle Nut with 3/4"-16 Dia./Thr
Low Carbon Steel Castle Nut with 1"-14 Dia./Thread
Steel Castle Nut with 5/8"-18 Dia./Thread Size an
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Steel Castle Nut with 5/8"-18 Dia./Thread Size and Plain Finish; PK25 Steel Castle Nut with 5/8"-18 Dia./Thread Size and Plain Finish; PK25
  • Item # 6YRL4
  • Mfr. Model # 354205G
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Steel, Material Grade Grade 5, Fastener Finish Plain,...More

Low Carbon Steel Castle Nut with 5/8"-18 Dia./Thr
Low Carbon Steel Castle Nut with 3/4"-10 Dia./Thr
Low Carbon Steel Castle Nut with 1"-8 Dia./Thread
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Low Carbon Steel Castle Nut with 1"-8 Dia./Thread Size and Zinc Plated Finish; PK10 Low Carbon Steel Castle Nut with 1"-8 Dia./Thread Size and Zinc Plated Finish; PK10
  • Item # 2GB85
  • Mfr. Model # 287082-PG
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Low Carbon Steel, Material Grade Grade 2, Fastener...More

Low Carbon Steel Castle Nut with 3/8"-24 Dia./Thr
Low Carbon Steel Castle Nut with 7/8"-14 Dia./Thr
Low Carbon Steel Castle Nut with 3/8"-16 Dia./Thr
Steel Castle Nut with 3"-4 Dia./Thread Size and P
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Steel Castle Nut with 3"-4 Dia./Thread Size and Plain Finish; PK1 Steel Castle Nut with 3"-4 Dia./Thread Size and Plain Finish; PK1
  • Item # 41UA15
  • Mfr. Model # U12040.300.0001
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Steel, Material Grade Grade 2H, Fastener Finish...More

Steel Castle Nut with M5-0.80 Dia./Thread Size and Pla
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Steel Castle Nut with M5-0.80 Dia./Thread Size and Plain Finish; PK100 Steel Castle Nut with M5-0.80 Dia./Thread Size and Plain Finish; PK100
  • Item # 38DH76
  • Mfr. Model # M12000.050.0001
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Steel, Material Grade Class 4, Fastener Finish Plain,...More

Carbon Steel Castle Nut with 5/16"-18 Dia./Thread
Carbon Steel Castle Nut with 3/4"-10 Dia./Thread
Steel Castle Nut with M6-1.00 Dia./Thread Size and Pla
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Steel Castle Nut with M6-1.00 Dia./Thread Size and Plain Finish; PK100 Steel Castle Nut with M6-1.00 Dia./Thread Size and Plain Finish; PK100
  • Item # 38DH77
  • Mfr. Model # M12000.060.0001
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Steel, Material Grade Class 4, Fastener Finish Plain,...More

Carbon Steel Castle Nut with 1-1/8"-7 Dia./Thread
Carbon Steel Castle Nut with 1-1/4"-12 Dia./Thread
Steel Castle Nut with 1"-8 Dia./Thread Size and P
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Steel Castle Nut with 1"-8 Dia./Thread Size and Plain Finish; PK5 Steel Castle Nut with 1"-8 Dia./Thread Size and Plain Finish; PK5
  • Item # 41UA10
  • Mfr. Model # U12040.100.0001
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Steel, Material Grade Grade 2H, Fastener Finish...More

Carbon Steel Castle Nut with 3/8"-16 Dia./Thread
Carbon Steel Castle Nut with 1"-8 Dia./Thread Size
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Carbon Steel Castle Nut with 1"-8 Dia./Thread Size and Plain Finish; PK5 Carbon Steel Castle Nut with 1"-8 Dia./Thread Size and Plain Finish; PK5
  • Item # 41UA17
  • Mfr. Model # U12050.100.0001
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Carbon Steel, Material Grade Grade 2, Fastener Finish...More

Carbon Steel Castle Nut with 7/8"-9 Dia./Thread S
Steel Castle Nut with M60-5.50 Dia./Thread Size and Pl
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Steel Castle Nut with M60-5.50 Dia./Thread Size and Plain Finish; PK1 Steel Castle Nut with M60-5.50 Dia./Thread Size and Plain Finish; PK1
  • Item # 38DH95
  • Mfr. Model # M12000.600.0001
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Steel, Material Grade Class 4, Fastener Finish Plain,...More

Steel Castle Nut with M8-1.25 Dia./Thread Size and Pla
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Steel Castle Nut with M8-1.25 Dia./Thread Size and Plain Finish; PK100 Steel Castle Nut with M8-1.25 Dia./Thread Size and Plain Finish; PK100
  • Item # 38DH78
  • Mfr. Model # M12000.080.0001
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Steel, Material Grade Class 4, Fastener Finish Plain,...More

Steel Castle Nut with M14-2.00 Dia./Thread Size and Pl
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Steel Castle Nut with M14-2.00 Dia./Thread Size and Plain Finish; PK50 Steel Castle Nut with M14-2.00 Dia./Thread Size and Plain Finish; PK50
  • Item # 38DH81
  • Mfr. Model # M12000.140.0001
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Steel, Material Grade Class 4, Fastener Finish Plain,...More

Carbon Steel Castle Nut with 1-1/4"-7 Dia./Thread
Carbon Steel Castle Nut with 1-3/8"-12 Dia./Thread
Steel Castle Nut with 1-1/4"-7 Dia./Thread Size a
  • TM

    Grainger Choice

  • GRAINGER APPROVED
  • Steel Castle Nut with 1-1/4"-7 Dia./Thread Size and Plain Finish; PK1 Steel Castle Nut with 1-1/4"-7 Dia./Thread Size and Plain Finish; PK1
  • Item # 41UA11
  • Mfr. Model # U12040.125.0001
  • Castle Nut, Nut Style Round Slotted Nut, Basic Material Steel, Material Grade Grade 2H, Fastener Finish...More

Results per page:  16 | 32 | 48

Castle nuts, or castellated nuts, are known for their distinct appearance - a nut with slots cut into the end, like the parapet of a medieval castle. Castle nuts are positive locking devices and used in conjunction with a fastener to lock. Find castle locknuts in steel, carbon steel and low carbon steel at Grainger.

Note: Product availability is real-time basis and adjusted continuously. The product will be reserved for you when you complete your order. More