very sturdy! pre-drilled the holes into the 4x4s and 4x6 and the only issue was on the 4x6, must have hit into a knot in the wood and when my 14 yr old son was using the ratchet, it was going in crooked and the bolt actually broke at the base of the wood. these are some cheap chinese bolts, the rest went in okay, but if your a stickler for quality, maybe go pick up 24 bolts at your local shop. so thats why i gave it 4of 5.