Will this 5400 mAh fit to my cam?

http://www.handy-town.net/product_info.php/refID/8/info/p1547_Akku-fuer-Panasonic-CGA-D54S-Li-Ion-5400mAh.html

Remember there is a hook beside the battery placment on the cam. Any experiences with these unoriginal batteries? Can I use