21. The expert from Germany presented the work being undertaken to transpose provisions for Deployable Pedestrian Protection Systems (DPPS) from UN GTR No. 9 into UN Regulation No 127 (informal documents GRSP-77-21, GRSP-77-22 and GRSP-77-23-Rev.1). The expert from the Kingdom of the Netherlands added that this was the first time Human Body Models (HBM) simulations were being used in the Regulation, complicating the work.