The Floyd Rose Original Tremolo typically comes with a block that is 37mm in height. This is the standard size that comes with most Floyd Rose Original Tremolo systems. However, they do also offer blocks in different sizes (32mm, 42mm, etc.) to fit various guitar body depths.
It's important to note that the block size needed can vary based on the specific setup of your guitar. You might want to measure the depth of your guitar's tremolo cavity or consult with a professional luthier to make sure you're getting the correct size.
Remember that changing the block size might also require changing the spring length in your guitar's tremolo system to maintain the correct tension balance. Always consider these factors before making changes to your instrument's hardware.