Replacement Office Chair Tilt & Lock Lever Base Plate Mechanism Medium 150x200

5 STARS.First off, I'd like to say a big thank you to the seller for posting my purchase so fast that I received it the next day :)Now the plate is a perfect fit for my seat. I just hacked off my old broken plate with a hammer and stuck on this new plate, bolting it in with the old screws from my broken plate as this item does not come with bolts of its own, so KEEP YOUR OLD CHAIR PLATE BOLTS IF YOU'RE PLANNING TO BUY THIS PRODUCT.The plate was a lot bigger than I thought. I still don't know what the big massive knob thing is for so I'll search into that. I was very surprised that the chair plate has a tilt mechanism (I guess I didn't read the product title or description properly), but this is a massive great feature to have as I think I broke my old chair plate because it wasn't flexible. As I kept rocking back and fourth in my chair, I kept on putting pressure on the plate which led to it cracking over time.So happy with this purchase, now I can get back to programming in a very comfortable position.