What's this window handle bolt?

[The Gauge]

The handle bolts on one of my upvc windows have decided to come loose today. Anyone know what this type of bolt head is called and the tool needed to tighten them? Don't want to butcher it with a wring sized screwdriver..

[The Rotrex Kid]

Looks like a rounded off Phillips to me…..

[The Gauge]

It could well be

It just doesn't look like a normal Philips head or similar.

• Edit, I think it was, I managed to tighten it but they will probably need replacing.

Edited by The Gauge on Wednesday 25th December 16:14