... bolt,usually thin nutSIZE240 mm *130mm *20mmWINDOWS SIZE128mmX70mmPULLING RESISTANCE400kgsNOTE(1)MATERIAL — ballproof PC, never break, stable and shapely.(2)BELT — ... safety belt material, double link without gaps , extra-heavy, more stable(3) CLAMP ... down design, two locking bolts, more firm and reliable HR-001 city bus plastic handle with advertising