Want to sound as bad as they look? Then you need the custom blue valves Bonzo Bad-Boy™ Blue-Bottles® 6L6 Valves Tubes for Guitar Amplifiers. These bad boys are matching pairs of high quality vacuum tubes specially custom re-styled so you can impress your guitar friends when they look in the back of your amp. Watch their faces when they realise you have something they could only dream of owning! Prefect for the blues and of course the elusive 'Blue Sound' - OK we were just kidding there!