I've been using nothing but these:
Click here. for years and years now on 3 different TT's. I have on occasion used the 1 pal. They do what they are designed to do, keep the wheel from moving. I do use them with my utility trailer all the time (single axle).
Put one facing each direction (I prefer the middle between the tires (when I have used them on the TT), and make sure you have them on both sided of the camper.
My Bal style, works very nice. Never had the trailer move with them in place.