We have a DB sub and a mackie srm350, this pole works perfectly and can put the mackie at a good height (well above head height if needed). The bottom of the pole is tapered so it can be fitted into the sub securely and the top has a rubber end to the speaker sits nicely on top.
The locking mech is very sturdy. One knob to adjust where the pin goes in and another to lock it in place. All very well made, and a great price on Thomann!
I would highly recommend all K&M stands for their quality and durability.