4-Pack 5/16-18NC Female Knobs

I lost a knob, had to replace it. I am going to talk about the Ladder. IT IS AWESOME! I have a pontoon boat, 3 dogs, 50 lbs, 85 lbs and 100 lbs! I can not pull them out of the water onto the pontoon. I also have a floating mat. We keep the mat at the bottom of the ladder. The dogs jump in (except the 100 lb dog, he goes down the ladder), they get on the mat, then easily climb up the ladder. Smaller dogs could probably easily climb up, there are 2 steps into the water from my boat and the steps are close together. My 50 lb can do it.