Tremolo Block

The tremolo block is a solid block of steel that attaches to the back (bottom) of a Strat-style tremolo bridge inside the guitar body. The strings pass through the tremolo block; the block also serves as the anchor point for the tremolo springs (which attach on the other end to a claw screwed into the body. Some manufacturers have experimented with titanium blocks to reduce weight, and the 2008 version of the Fender American Standard Stratocaster tremolo block is copper-infused to increase its mass without increasing its size.