RS PRO Black 4-Arm Clamping Knob, M8

  • RS Stock No. 686-632
  • Manufacturer RS PRO
Technical data sheets
Legislation and Compliance
RoHS Certificate of Compliance
COO (Country of Origin): CN
Product Details

RS PRO Phenolic Star Male Handwheel Knobs

Knobs are used in a wide variety of applications in our day-to-day lives and perform many functions, from being used as fixed handles to being used to tighten, loosen, adjust, clamp and push other components or pieces of equipment. They are used in various applications, from industrial and construction machinery to audio and visual equipment.

These star shaped handwheels – also known as multiple lobed handwheels– provide an easy-to-grip shape. This variation features four lobes, but other models will have varying numbers depending on the grip and pressure required. The knobs are fitted with a protruding screw insert (male) made from a combination of wood-filled impact-resistant thermoplastic bodies and zinc-plated steel inserts. Zinc-plated steel provides wear resistance for the threads to ensure that the threads last throughout general use and are not easily damaged or sheared.

Male knobs: M6 x 13mm (RS 686604), M6 x 25mm (RS 686610), M6 x 40mm (RS 686626), M8 x 20mm (RS 686632), M8 x 25mm (RS 686648), M8 x 40mm (RS 686654).

Features & Benefits

  • Wood-filled phenolic knobs

  • Zinc-plated steel threaded studs

  • Made to BS771 standards

  • Working temperature range of -30°C to +140°C

  • Tolerant of weak acids, with excellent resistance to chlorinated hydrocarbons


These star-shaped handwheel knobs are used in a variety of applications, with the shape providing an ergonomic grip for user comfort and added torque to be applied by hand. They are commonly used as fixing or fastening solutions in a variety of industries, including:

  • Access doors

  • Drawers & panels (domestic and industrial)

  • Clamps and fixtures

  • Machinery

Attribute Value
Thread M8
Thread Diameter 8mm
Thread Length 20mm
Knob Shape 4-Arm
Mounting Type Threaded Stud
Knob Diameter 50mm
Insert Material Alloy
Colour Black
26 In stock for delivery within 2 working days
Unit of sale: 1 Pack of 10
(exc. VAT)
(inc. VAT)
Per Pack
Per unit*
1 - 4
5 - 9
10 - 29
30 +
*price indicative