Hello, after i posted my question about what is a wide wooden timber many guys answered my questions, first i say thanks to all the guys that helped me, they says that it refers to a 4x4 wood timber, today i went to many stores that sells wood, and i purshased an 4x3 inch 3 foot wood plank for about 12 dollars. but when i lifted the board at the wood store , i found that the board is light for me and i thought that grip guys willl help me with some advices to add some resistance to the plank, pl