11. The expert from Japan introduced ECE/TRANS/WP.29/GRSP/2021/19 on the safety-belts of seat positions equipped with the lower ISOFIX anchorages. He also introduced presentation GRSP-70-32 highlighting that the maximum values of pelvis acceleration and lap belt force of rear dummies were larger than those of front dummies. The expert from OICA introduced GRSP-70-25 showing that data from the expert of Japan showed that for booster seats secured by both safety-belt and ISOFIX could cause slack in the belt system which leads to increased dummy loadings. Therefore, he suggested that booster seats with ISOFIX attachments should be type approved according to UN Regulation No. 129 as “specific to vehicle” and not as “universal” or “i-Size”. GRSP agreed to resume discussion on the proposal at its May 2022 session.