lagan single lever kitchen tap ( ikea )

[oeeeeeeg]

Hi there, help needed. I'm trying to replace the cartridge in this tap but can't work out how to undo the small screw on this. It doesn't seem to be slotted for a screwdriver. Is there a standard screw that fits all taps and what should I use to get it out.
Cheers for any help.
P.S. link below for tap (exploded view on PDF) if that helps.
http://www.ikea.com/gb/en/catalog/products/90085028/

 

[xr4x4]

What screw?

 

[oeeeeeeg]

What screw?

If I pop the blue/red plastic thing out under the handle there's a small screw thing but it's neither slotted nor Phillips.

 

[seco services]

You'll more likely find it being a allen key you need.

 

[oeeeeeeg]

You'll more likely find it being a allen key you need.

Sorted mate it is an Allen key and, even better, IKEA are sending me the cartridge and key free of charge.