Heel width :63-64 mm. The hole: 18 mm. nut 42 mm / 38mm. Easy to install, Less troubles: Car fillers between seats attaches to the seat belt catch via built in slot. They will move with the seat and no need to readjust or reinstall. Provides 100% Gap Coverage in front of, surrounding and behind seat belt catch Back material type: hard-maple Neck material type: hard-maple HIGH CONSTRUCTION]- The fretless 4-string bass guitar neck is made of high- maple wood for excellent durability and stability. · [Versatile 20-Fret ]- This... Fretless Maple 21 Frets Neck For Electric Bass Guitar Neck Part Replacment 5 String - Ali Bass Neck Each neck is unique in grain patterns. Roasted Maple Wood 4 String Jazz Bass Style Neck, 20 Frets Body material type: Solid Wood Maple fingerboard vine inlay gloss finished scale length 34 inch .nut 42 mm/ 38mm.tuner hole 18 mm.hell width 63-64mm Neck shape: C. Our factory can custom make you need. Fretless Maple Electric Bass Guitar neck 20 frets