Applications in the food industry demand due to the contact with water and cleaning chemicals notably high requirements on the used cylinders. The company SMC meets these requests with the new serial HY. Four different models enable to find for any applications the appropriate cylinders and to be ISO / VDMA conform constructed. Due to a special wiper ring the constancy of water and thereby the lifetime could be increased tremendously. The particular plain surfaces, the avoiding of dead spots and discharged Auto-switch rail make sure that no residues cling to the product.