Arc Lab Motorsports and Fabrication. They make a great pole and shuttle system, and their inline transducer mount makes switching between modes really easy while assuring your transducer doesn't rotate on the shaft knocking it out of alignment. Their shuttle and docking station are phenomenal in a boat, while still leaving you with mobility to take it to other boats, ice fishing etc.
Brew City's pole is probably the most widely known and used, very durable, carbon fiber, easy availability from most retailers. They make a simple attach system that will work with rails or tracks on your boat that allows for easy on/easy off when traveling. I added a ram claw to mine and have no problems rotating it to the stored position and clamping it in near the transducer and going down the highway 70mph.
TKI is built very well. I havent used their pole, but their other products and customer support are second to none!
There are many others out there, I don't know if any of them are any better or any worse than the others, it just comes down to availability to you and the price factor you wish to spend.
