RS PRO Black, Self-Colour Steel Hex Socket Countersunk Screw, DIN 7991, M4 x 20mm

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R 301,66

(exc. VAT)

R 346,91

(inc. VAT)

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RS stock no.:
292-445
Distrelec Article No.:
304-17-403
Manufacturer:
RS PRO
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Brand

RS PRO

Imperial or Metric

Metric

Thread Size

M4

Length

20mm

Head Shape

Hex Socket Countersunk

Material

Steel

Finish

Black, Self-Colour

Thread Type

Metric

Thread Pitch

0.7mm

Standards Met

DIN 7991

COO (Country of Origin):
CN

RS PRO M4 x 20 mm Hex Socket Countersunk Screw Black, Self-Colour Steel


Want to prevent screws from sticking out of your equipment or surfaces? Turn to this countersunk fastener from RS PRO. It has a high strength-to-weight ratio thanks to its stainless steel material, while the black oxide coating enhances its thickness and resistance to corrosion. This means it can withstand heavy-duty applications in tough industrial environments.

For fast and simple installation, use an Allen or hex key to tighten the screw. As it's small in size, it can easily fit into tight spaces. This type of screw is commonly used for domestic and commercial applications, including woodworking, DIY constructions and building panels.

Features and Benefits


  • Black, self-colour finish

  • Hex socket countersunk head shape

  • Length of 20 mm

  • Steel material

  • Thread pitch of 0.7 mm

  • M4 thread size

  • Metric thread type

    • RS PRO Metric Countersunk Hexagon Steel Screw


    RS PRO hexagon socket countersunk screws are an excellent choice when you need a fastener to sit flush or below the surface of your material.

    These popular metric thread countersunk screws are produced in 10.9 grade steel and are designed for light duty applications where space is limited. These fasteners have a black finish which ensures an attractive, quality appearance and finish wherever they are used.

    These screws fasteners can be tightened or undone using an Allen key.

    Features and Benefits:


    Various thread sizes available, including M3, M4, M5, M6, M8 and M16

    Countersunk – the head does not stick out so that nothing can hit it and interfere with the operation of the application

    Also used in many internal joinery applications

    Have the marking on the head

    More resilient than 8.8 grade

    Nominal strength of 1040 N/mm²

    Yield strength of 940 N/mm²

    Requires a Hex key / Allen key

    Typical Applications:


    Although uses may vary, as standard, these screws are fasteners for industrial equipment or machines which requires parts to be fixed onto a surface or together. The socket will need to be the same metric thread as the screw itself. As an example, some of the types of uses would be:

    Woodworking

    Domestic applications

    Fasteners and fixings

    Machine tooling and repair

    Security guarding

    Panel Building

    Electronic applications

    Automotive industry

    Medical applications

    Facilities and maintenance applications

    FAQs
    What is a socket screw?


    Socket screws are defined by their name. They are a type of threaded bolt which screws into the intended socket. There are various thread sizes and lengths and can be used for both industrial and personal purposes. Good quality and reliable RS PRO socket screws ensures the fixing will remain strong and stable, whatever the application.

    Note

    Requires a Hex key
    We offer a range of hexagon countersunk socket screws in black self-coloured steel, available in various thread sizes and lengths. Refer to the Datasheet and Range Overview download file for details.
    If black oxide self-coloured steel is not what you are looking for we also offer steel hexagon countersunk socket screws with a BZP finish or alternatively A2 (306) and A4 (316) stainless steel.

    Standards

    Threaded in accordance with DIN 7991

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