-Inhaler chamber-Optimizes the delivery of MDI asthma medication.-Compatible with most MDI (metered dose inhaler)actuators.-Helps target medicine to your lungs.-Anti Static plastic ,Latex free-with different sizes of mask for pediatric ,child ,adult useItem no.size Chamber SizeQty/ctnHCA01Adult160ml50HCA02Child160ml50HCA03Pediatric160ml50HCA04Adult160ml50