💧→🕳️

#exocrine secretion #duct system #gland #epithelial secretion #pore #secretion pathway

🧊🔥🌬️⬜

#CAVH #air conditioning #climate control #controlled air #duct system

🔩🪚➡️

#metal ducts #galvanized steel duct #airflow #duct system #pipe network #industrial ductwork