4000 size = perfect for bass fishing with rods of around 9ft casting about one ounce (30-60g max) or for use with an entry-level spinning rod between 7-9ft which is likely to be thicker
In our Minn Kota Terrova review, were going to cover the good and the badand were happy to say its mostly good
DONT pick the weight up, slide it

We love the Folbe Advantage Rod Holder so much we felt compelled to offer them to our customers. When we first used the Folbe Quick Release Rod holder on a guided trip years ago. We immediately knew it was the best Rod Holder we had ever seen. Fishing with the Folbe Quick Release fishing rod holder means that you can handle any striker or serious rod take down quickly and efficiently. No More Fumbling trying to get your rod out of the holder. Just reach down and lift the rod straight up out of the Folbe Rod Holder, It's that fast. From light biting pike to that heavy-hitting catfish that has your rod buried, just pull straight up and you're out in the fish fighting position. Only the best marine grade materials are used making the Folbe Advantage Rod Holder tone of the strongest rod holders on the market. The Folbe Advantage Rod Holder is made from non-corrosive materials with stainless hardware for fresh or saltwater use. Depending on where and how you mount the rod holder, it can be adjusted horizontally 360 in 12 separate steps at 30 each. Vertically, the rod holder can be adjusted up to 180 in 8 separate intervals at 22.5 each. The Folbe Advantage holds any size Fishing Rod with Handles up to 1.5" in Diameter. We really like it for larger Rods like our Sturgeon Rod and other offshore style rods. For Salmon Rods, Bass, Trout, and most inshore fishing we suggest that you use the Folbe Advantage Junior

SPORTSSTUFF 53-2030 4K Booster Ball for Towables (Amazon Link Ad) This is not a tube, but something you add if you want to enhance the experience
Fly fishers can choose from a good selection of sizes and styles, but the rest of us have less choice