Once you decide to use the beautiful lightweight t-bar you will need a coater cover to make it work - like a paint roller needs a roller cover to hold paint. DuraTool makes these with angled ends so you can coat the floor right up to the baseboard without getting finish on the baseboard itself. Soft, fine bristles that work with both oil-based and water-based finishes.
These are tough enough to last for several projects, as long as you take care of them. This means never letting them dry out! In between coats (or even between jobs) keep your coater soaking in the same solvent that your finish is based on (if you're using an oil-based polyurethane, keep your coater soaking in paint thinner, but if you're coating with a waterborne finish, submerge the coater in water). We also sell a nifty tube HERE that for soaking your coater cover, which is cheaper than buying a second coater.
The t-bar comes in two sizes, this cover is for the longer 18" size. Need a smaller sizer? We sell a 12" coater cover here.
Wait, did you forget to buy the t-bar itself? Not to worry; buy it