HAL SnPb (lead-tin) is nowadays allowed only in certain technology fields such as medicine and aeronautics. HAL SnPb has been replaced by HAL lead-free. If the surface finish is specified only as HAL or HASL, typically the lead-free version is meant. HAL SnPb is suitable for standard SMD, but shows weaknesses in fine pitch applications. A chemical surface is preferable for finepitch (see also HAL vs. chemical gold).