All PSL plates are equipped with DN ISO 16 and / or ISO 19 fl¬at face couplings, since both can be mounted in the same seats. The couplings are secured to the plates with highly-resistant elastic rings that allow them to rotate, thus avoiding accidental unscrewing or potential damages to the hydraulic pipes during assembly or usage. All the couplings are available with several connection threads according to customers’ needs and the mobile part is equipped as standard with an integrated decompression system that allows the two half-plates to be connected even in the presence of residual pressure on the male side.