[M18 (P=1.5)]

[M24 (P=1.5)]

■ Shape: Grooved nuts (2 types) Low shape
The top of the hex nut has 6 slotted cylindrical protrusions to prevent loosening and falling off. It is also lower in height than regular slotted hex nuts.
To tighten and secure the thread, the pin called "split pin" is inserted into the slot of the other bolt to prevent loosening and falling off.

■ Thread Shape: Fine
Finer than the nations most standard pitch (coarse) prescribed by ISO (International Organization for Standardization) standard. Compared to coarse threads, it has a shallow valley and a larger cross-section area which makes it less likely to loose. Please note that there are multiple sizes of pitch depending on the thickness of the screw. Primarily used where precision is required.

■Material: Iron
"Iron" is "steel" and is an alloy of iron containing carbon.
Although it is commonly used in many circulations, it is cheap materials, but due to the downside of it is easy to rust, many surface treatments will reduce corrosion.

■Surface treatment: Trivalent white
It has the same corrosion resistance as "chromate" and has the same possibility of imitation self-healing.
Unlike hexavalent chrome, it is non-toxic and compliant with RoHS directive. So it is used as an alternative to unichromate/chromate.
Color is "Silver Color".

Product Features:
Shape
It is used with 2 pins such as split pins.

Features
By inserting the pin hole of the bolt and the nut groove of the other material, the nut prevents it from rolling around.
Ready-made products come in 1 and 2 types (standard 1 to 4 types), and can be divided into lower and high types.
One type is commonly known as castle nut.