Alphasense H2S gas sensors are available in different sizes and models.
Compact Hydrogen Sulfide sensors:
H2S-BH,H2S-BE,H2S-B4,H2S-B1
Miniature H2S sensors:
H2S-D4
Small H2S sensors:
H2S-AH,H2S-AE,H2S-A4,H2S-A1