From plastic to steel...YES!!!
My heavy, sturdy, 18" sub cabinets actually came with PLASTIC cups installed on the top for the speaker pole to set in. Can you believe it? So, I call Sweetwater, and they point me in the right direction and I get this. Big deal you say? Hmm...plastic, fragile...Steel, unbendable...No doubt about it. My mains are sturdily being held in place now from a small, inexpensive OSS cabinet insert. Thanks OSS and Sweetwater for an awesome deal!