Clamping blocks are installed on the clamping cart of log band saws, to fixate the wood to be sawed while it is passed through the band saw. In most cases, several such blocks are mounted on a clamping cart to prevent a slipping of the wood. With the help of hydraulic clamping hooks (see Spannhaken), which can be moved independently from the blocks, the trunks can be fixated in their position very close to the clamping blocks.