Fit for chamfering irregular shape and arc work piece. 可用不規則形狀及圓弧形狀加工件使用。
Or, they can be more loosely bound, irregularly shaped groupings of up to several thousands of stars, like the open clusters shown in this image. 或者他們能更加疏松的聯(lián)合在一起,由數千顆恒星所組成的不規則形狀,就象這張圖中的疏散星團。