Isikrufu esilungisekayo sezimboni esenziwe nge-chrome vanadium nesiphetho se-phosphate nesibambo se-bi-material ukuze uthole ukunethezeka okwengeziwe. Umhlathi ongu-15degree uvumela isikrufu ukuthi sisetshenziswe ezindaweni eziwumngcingo njengoba kudingeka ukujika okungama-degree angu-30 kuphela. Ukuvuleka komhlathi okubanzi kwandisa ububanzi bosayizi webhawodi okuzosetshenzwa kuwo. Ukungaphumeleli ekugcineni komhlathi onyakazayo kunikeza isenzo esingcono uma isikhala silinganiselwe. Isibambo sihlinzeka ngokulingana kwesandla okunethezekile. Idizayinelwe futhi yakhiwe ukuze: ISO 6787-1982, ASME B.107.8M-1996, BS 6333-1995, DIN 3117-1988, JIS B4604-1976 kanye ne-SABS1211.
| L (mm) | Amandla (mm) | T (mm) | D (mm) | Isisindo (g) |
I-ISO (Nm) |
| 157 | 24 | 20 |
52 | 140 | 85 |