The caixa is type of snare drum. It's usually 12" in diameter, from 5 to 20cm deep and has snare wires strung across the top playing surface. The two ends are held together with six tension rods with tuning nuts on the bottom side.

The caixa is a lightweight drum with a distinctively high and dry sound. It is also very loud!

The caixa can be played slung over the shoulder with a strap, or resting on one arm if you really want to impress the punters.

On its own, the caixa may not sound like much, but as soon as a few play in unison their true power is unleashed. The caixa section maintains the upper end of the samba rhythm (with the surdos at the lower end) while also injecting a healthy dose of the carioca swing. The different patterns played by the caixa section are one of the important aspects that give a bateria their distinctive sound.

Here is a great video of Salgueiro Mestre Marcao and Carl Dixon cutting it up on the caixa.

As one of the most technical instruments, the caixa is best suited to experienced players and kit drummers.