Hi. I have rb411 board with level 3 license and routeros v5.16. i am planning to buy r52hn wireless card. i want to learn that r52hn compatible with my board ? i searched internet i found nothing 
sorry for my english. thanks
Yes, all RouterBOARD devices are compatible with all R wireless cards.
http://routerboard.com/R52Hn
yes, this card will be able to work without any problems on the board.
Just notice, that it will work either as client or in mode=bridge as that is the limitation of the RouterOS license of the mentioned device. For AP mode you need a RotuerBOARD model that has L4 license
Thanks for your answers 
Have a nice works