ILCA 4 Back Of Boom Outhaull - 29mm blocks

The ILCA 4 Back Of Boom Outhaul system is the original and classic , its built up of multiple parts : the block around the mast , the primary line , and another block that attaches to the cleat in the middle of the boom. 

in our opinion there is little difference between the two,  front of boom and back of boom systems both allow for good calibrations and smooth running rope . at the end of the day it comes down to personal preference and what you are used to. 

The 29mm blocks are one of the most sturdy and reliable blocks that are very rare to break and can last a extremely long time with good effeciency