Phillips pan head SEMS screw with integrated washers (P4)

This is a pan head Phillips screw with pre-assembled components: a spring washer and a small flat washer.

It helps prevent missing or forgetting washers and improves assembly efficiency.

It is also known as a SEMS screw or pre-assembled washer screw.

Depending on the washer combination, variants include:

• P-2: spring washer only
• P-3: spring washer + flat washer
• P-4: spring washer + small flat washer

📌 In the P-4 type, the spring washer conforms to JIS standard (SW), and the small flat washer conforms to the JIS legacy standard (small type round washer / 小形丸座金), both pre-assembled.

Standards supplied: JIS B 1188, GB 9074.4, GB 9074.8 (small head)

The pre-assembled washers are components that comply with the same international standards as the screw body.