Aluminium and aluminium alloys . angles . dimension and form tolerances 铝和铝合金.角材.尺寸和形状公差
Angle with nuts 带螺母的角材
Construction , beams and furniture . allergy sometimes caused by fine dust on sawing , and resin easily stuck to saw - teech 建筑用材?梁?车只角材?合板用旋切单板?锯屑易使皮肤过敏?木材中所含树脂常黏滞在锯齿中。