Galvanized Countersunk Cross Tapping Screws - Top Quality from China Suppliers and Factory
| Thread specifications | ST2.2 | ST2.9 | ST3.5 | ST4.2 | ST4.8 | ST5.5 | ST6.3 | ST8 | ST9.5 | |||
| P | Pitch | 0.8 | 1.1 | 1.3 | 1.4 | 1.6 | 1.8 | 1.8 | 2.1 | 2.1 | ||
| a | Max | 1.6 | 2.2 | 2.6 | 2.8 | 3.2 | 3.6 | 3.6 | 4.2 | 4.2 | ||
| dk | Max | 3.8 | 5.5 | 7.3 | 8.4 | 9.3 | 10.3 | 11.3 | 15.8 | 18.3 | ||
| Min | 3.5 | 5.2 | 6.9 | 8 | 8.9 | 9.9 | 10.9 | 15.4 | 17.8 | |||
| k | Max | 1.1 | 1.7 | 2.35 | 2.6 | 2.8 | 3 | 3.15 | 4.65 | 5.25 | ||
| Slot Number | 0 | 1 | 2 | 2 | 2 | 3 | 3 | 4 | 4 | |||
| M1 | Cruciform | 1.9 | 3.2 | 4.4 | 4.6 | 5.2 | 6.6 | 6.8 | 8.9 | 10 | ||
| M2 | Zigzag slot | 2 | 3 | 4.1 | 4.4 | 4.9 | 6.3 | 6.6 | 8.8 | 9.8 | ||
| y | Reference value | Type C | 2 | 2.6 | 3.2 | 3.7 | 4.3 | 5 | 6 | 7.5 | 8 | |
| Type F | 1.6 | 2.1 | 2.5 | 2.8 | 3.2 | 3.6 | 3.6 | 4.2 | 4.2 | |||
| Type R | / | / | 2.7 | 3.2 | 3.6 | 4.3 | 5 | |||||
How to choose a suitable self tapping screw
Frequently Asked Questions (FAQ)
The thread specifications cover standard sizes from ST2.2 up to ST9.5, including details on Pitch (P), Head Diameter (dk), Head Height (k), and specific slot dimensions.
You should select screws based on the hardness of the installation material. For harder materials, high-strength screws with appropriate lengths and diameters are required.
Coarse and fine threads are designed to accommodate different target materials to ensure optimal grip strength and prevent stripping.
Pentagonal head self tapping screws offer superior sturdiness compared to ordinary round head screws, although they typically come with a higher cost.
According to the specifications, they are available in Cruciform (M1) and Zigzag (M2) slot configurations, with slot numbers ranging from 0 to 4 depending on the size.