Bomber recommends the Buster Roller Tbar as an alternative to the Barrie Gag. This is a kinder bit and achieves a similar result.
The Bombers Buster Roller Tbar Polo Gag bit is recommended for horses that are built downhill.
This is a very strong bit, with the highest level mouth pressure.
The TBar is a specialisation which aids in turning, especially for young horses.
Size note: the Bombers Buster Roller is a broken bit that bends across the top of the tongue. 10mm should be added to a straight mouth measurement, e.g. a 125mm Buster Roller bit will fit a horse that measures 115mm-120mm straight across the mouth.
The Buster Roller has a small link in the middle that increases bar and tongue pressure making this mouthpiece sharper than conventional link bits. The increased pressure on the horse's bars will lift the head and the roller will increase pressure on the tongue bringing the chin in. Best suited for a horse with a low head carriage and which leans on the bit.