there are 4 differenct options:
3 wood - this obviously isnt it
Driver - 2.2 in
Oversize - 2.4 in
XLT - 3 1/8 in

Oversize, but do not waste your money. Brush-T is a gimmick. They break easily, leave marks on your club are distracting and other golfers will laugh at you. Try Stinger tees instead. They look like regular tee, do not leave a mark (natural wood) and are low friction, just like Brush T. You can find them in golf stores and on eBay.

Driver - 2.2 in

brush tees suck just get some normal tees

Oversize or xlt

Orange, l think they are the Oversized. l agree with the other posters they are a gimmick. If you do not keep it in the ''bullet'' it wears fast. l rather use a tee that l can easily put in my pocket. Personally, l use zero friction tee is l have never broken one!

Brush tees r terrible. Mine was pretty much useless after 2 trips to the range. The bristles become so messed up that the tee wo not hold a ball.

As someone else suggested, get a pack of zero friction tees. You can buy a 50 pack at golfsmith for around 6 bucks. These look like real tees & still have little friction. l have yet to break one as well, though l do not use them when l am teeing off on Par 3s. Best kind of tee out there & people wo not make fun of you.

2.4 would be the correct height. l use a 460cc driver and use a 2.5 inch step tee.