KS hollow blocks are medium-format masonry blocks made of sand-lime bricks with a hole content of 15 – 50 % of the cross-sectional area. This also allows for lower bulk densities than block blocks. As a "normal" hollow block block, they are bricked with approx. 1 cm high bearing joints made of normal mortar, as a flat block with approx. 2 mm high bearing joints made of thin-bed mortar. In the case of hollow blocks with a tongue and groove system on the end sides, butt joint mortar is usually not necessary.
Source: bauwion
see also product example: ☛ KS -Original
