what size bolts for bed strips??

[72step]

Thanks for the info guys. I was looking at my bed strips last night again and they have rust and those grooved bolts I had to cut off are all stuck in there. Then I did kinda messed up the angle strips a little when I was dealing with those rusty bolts so I'm just gonna spend a little money and get the stainless bolt kit and stainless angle strip covers and stainless unpolished strips. Might as well put a more permanent solution onto composite which will make my bedfloor 100% maintenance free. This bed floor business is a lot of work and I only want to do it once. Thanks....Matt