1:QBK-15 Pneumatic Diaphragm Pump 2:Caliber:10mm,15mm,25mm,40mm,50mm,65mm,80mm,100mm ... QBY air operated diaphragm pumps is the third generation of pneumatic diaphragm pump,with the trait of long life and low malfunction ... some uneasy flowed medium,with the merits of self-pumping pump,diving pump,shield pump,slurry pump and impurity pump,etc. QBK-15 Pneumatic Diaphragm Pump