Hello. I'm pretty sure I have the css sprite technique down. I have no problems on my imac in either Safari / Firefox and Opera. I even have no problems with the technique in IE! Whoop. The only place I'm having a problem is on my girlfriends Mac book in Firefox!? I created this page to isolate and test the problem (the normal and hover states should look exactly the same for purposes of this example). http://andyjamesnelson.co.uk/example/ Hopefully if you look at the page and check the source etc you will have no problems. The problem on the macbook is there on hover the tick moves ever so slightly to the left. Say 1px!!!? I have checked and double checked the source png and the two states are identical. The other issue seems to be that the edge fidelity of the tick itself is all blurry!? Can anyone help with this its really bugging me. Andy.