GT Agressor 3.0 Handlebar Size?

[redvision95]

I'm wanting to replace the handlebars on my GT Agressor 3.0 but need to know what size handlebars they take, was wondering if anybody on here knew? I've googled it but seeing mixed answers of 25.4mm and 31.8mm.
Anyone able to tell me what size I need?

 

[Ajax Bay]

Measure them. Much the safest option. If you haven't got calipers, use a flexible (eg sewing) tape measure to measure the circumference and divide by pi (@vernon - you will not be forgotten). http://www.gtbicycles.com/usa_en/tech-downloads/ Suspect inch.