Is OPOS Required for POS .NET

Hi all, I am planning to buy a cash drawer to write my own POS system. However my problem is after reading a while on OPOS and POS .Net I am a little confuse as to how to open a cash drawer.

I am currently looking at a RJ232 cash drawer, lets say the vendor does not provide any OPOS driver. Would I still be able to open my cash drawer using POS .Net? Or would I need a cash drawer with a USB port in order for it to work? 

I am currently looking at this cash drawer http://product.code-soft.com/60-ec-410.html.