蝶型螺母

例句：

1. 1. The screws are all in the same size, which makes it easy to install the nut.
   螺丝大小相同，安装螺母变得简单。
2. 2. The engineer used a special tool to tighten the nut on the bolt.
   工程师使用特殊工具将螺母紧固在螺栓上。
3. 3. The nut is designed to fit perfectly into the hole, ensuring a secure connection.
   螺母设计得能完美地插入孔中，确保连接牢固。