Rear Shock Advice

beardwithabike Posts: 195
edited April 2010 in MTB buying advice
I have a Specialized Pitch Comp 2009 ... e-ec001433

and want to replace the rear shock (X Fusion O2R with rebound adjust. 7.875x2.25") with one that locks out for the uphill climbs. I was looking at getting a Fox Float but dont really know what spec / sizing all means??

Any advice or guidance please?