Which screw size is this countersink bit designed for?

With a 16.5 mm diameter and a 90° countersink angle, it is sized for M8 countersunk screws.

What type of shank does this countersink bit have?

It features a 1/4 inch external hexagon shank, compatible with standard bit holders, drills, and impact drivers.

Which materials can be machined with this bit?

This TiAlN-coated HSS bit is suitable for non-alloyed and alloyed steels up to 900 N/mm², aluminum, and brass.

Can this countersink bit be used in an impact driver?

Yes, thanks to its specialized geometry and TiAlN coating, this Fein Vario tool is rated for impact driver use.

What is the total length of this countersink bit?

The total length of this tool is 60 mm.

FEIN 63901080010 VARIO 90° taper countersink bit 16.5 mm M8

Name: FEIN 63901080010 VARIO 90° taper countersink bit 16.5 mm M8
Brand: FEIN
SKU: 08118081
Price: 44.8 EUR
Availability: InStock

Supplier number: FEIN 63901080010 | EAN 4014586476865

Recommended Retail Price €53.97

44.80 tax incl.

€37.02 excl. VAT (incl. all environmental contributions)

On stock - immediately available | we have 4 products in stock.

Ordered before 20:00 - delivered tomorrow 03/10/2026
Shipping costs €11.99 VAT included | Free shipping for orders over a total amount of 125 euros
Delivery by DHL

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Clean countersinking with Fein

Practical benefits

High wear and heat resistance: Made from hardened HSS with a TiAlN coating, this bit withstands temperatures up to 800 °C while maintaining sharp cutting edges.
Optimized for impact drivers: The specialized cutting geometry ensures chatter-free countersinking in steel, aluminum, and brass, even under high speeds and impact action.
Secure hex shank connection: The 1/4 inch external hex shank delivers solid torque transfer and prevents slipping in standard bit holders during demanding jobs.

In a nutshell

The right choise for

With the Fein Vario 90° countersink bit, you prepare clean, deburred holes in steel, aluminum, and brass for countersunk M8 fasteners. Built from hardened hss with a heat-resistant TiAlN coating, it retains its sharp cutting edge during demanding drilling tasks up to 800 °C. The optimized cutting geometry allows smooth, chatter-free countersinking without snagging, even under high speeds and impact action from an impact driver. Thanks to the 1/4-inch external hex shank, it locks securely into standard bit holders for direct torque transfer without slipping. This ensures flush-mounted screw heads and neat, safe metal assemblies every time.

Product information FAQ

€44.80

In stock - tax incl.

Key features according to our expert

Large diameter: 16,5
Shank size: 1/4 inch
Shank type: External hexagon
Countersink angle: 90 °

Product description

VARIO 90° taper countersink bit 16.5 mm (M8)
Long service life, thanks to high material strength (64 HRC), special cutting geometries suitable for impact screwdrivers and a TiAlN (titanium-aluminium-nitride) coating. The accessories are low-wear and low-friction as well as heat-resistant up to 800 °C and can therefore be used with high turning and impact frequencies in steel up to 900 N/mm2. Optimally suitable for the following materials: unalloyed and alloyed steels up to 900 N/mm², aluminium, brass.

All Features

Large diameter: 16,5
Shank size: 1/4 inch
Shank type: External hexagon
Countersink angle: 90 °
ø: 16.5 mm
L: 60 mm
Strength: 64 HRC
Tool holder: VARIO bit shank
Coating: Titanium-aluminium nitride (TiAlN)
Material: HSS
Heat resistance: max. 800°C

Brand FEIN
08118081
EAN 4014586476865
Supplier number FEIN 63901080010

Frequently asked questions about this product

Answered by specialists

Which screw size is this countersink bit designed for?: With a 16.5 mm diameter and a 90° countersink angle, it is sized for M8 countersunk screws.
What type of shank does this countersink bit have?: It features a 1/4 inch external hexagon shank, compatible with standard bit holders, drills, and impact drivers.
Which materials can be machined with this bit?: This TiAlN-coated HSS bit is suitable for non-alloyed and alloyed steels up to 900 N/mm², aluminum, and brass.
Can this countersink bit be used in an impact driver?: Yes, thanks to its specialized geometry and TiAlN coating, this Fein Vario tool is rated for impact driver use.
What is the total length of this countersink bit?: The total length of this tool is 60 mm.