What standard, flush head type bolt offers the largest diameter head?

是哪个标准的螺栓其冲出的头型极大于头部直径？

youdao

Kingfishers wedge themselves into water with a streamlined beak that gradually increases in diameter from tip to head, letting water flow past.

翠鸟流线型的长喙从尖端到头部的直径是逐渐增大的，潜水时会让水流向身后。

youdao

One millimetre (or the diameter of the head of a pin) is equal to one-million nanometres.

1毫米(或一个大头针头部的直径)等于一百万纳米。

youdao

The students' effort had a head diameter of 88.9 cm (35 in) and a shaft width of 35.24 cm (13.87 in).

CNN: February 5, 2013 -- Updated 1840 GMT (0240 HKT)

The Medicines and Healthcare products Regulatory Agency (MHRA) has issued new advice saying patients with these large head diameter metal-on-metal hips will need monitoring for the life-time of the implant.

BBC: Annual checks for patients with all-metal hips

But concern has been emerging for some time about certain types of metal-on-metal hips, in particular those where the ball head has a diameter of 36mm or more.

BBC: Annual checks for patients with all-metal hips