第三，关于纺锭轴承及锭脚的清洗问题。

Third, about spindle bearing and spindle foot's clean question.

莱托斯假设你已经购买了该软件的保护usb接口纺锭关键但你这个产品是用在一些电脑，但在不同的时间。

LetOs suppose you have purchased the software protected by USB HASP KEY, but you want this product to be used on several computers, but in different time.