You can use these countersunk steel screws from RS PRO when you need reliable fasteners to join chipboards or wooden boards. Their thread goes all the way up to the underside of the head, which makes them useful when you require an extra-strong hold.
These screws are made of A2-grade stainless steel for added resistance to corrosion and wear, so you can be sure they will last a long time in your outdoor applications. They feature a Pozisquare or Pozidriv head, which allows you to apply greater twisting force than you could when using screws with a slotted drive. This helps ensure the boards are firmly connected.
The screws come in a box of 100 which means you'll have plenty of them in stock. They also meet Restriction of Hazardous Substances (RoHS) standards, so you can rest assured they contain only minimal amounts of any harmful substances.

• Pozidriv drive type
• Countersunk head shape
• Length metric of 20 mm
• Stainless steel material
• A2 304 stainless steel type
• Thread size of 4 mm