They are shimano PD-M520, a cheaper alternative to speedplay frogs, the guy at my bike shop said if i couldnt get out of these then there is no hope!! So far i have managed to get out of them. Last night i took a tumble, got tire stuck in groove in road, damaged my knee got a lot of road rash and bruising, but tomorrow i am riding a big charity ride so fingers crossed i make it
Hope this helps