I have a total of 3 of these dosers. if your looking to setup a dosing system these are a great option. incredibly reliable and very consistent. these are quality dosing pumps. I have a timer as well lll include in the mix which retails for $20. its digital and can control all the pumps. buy all 3 dosing pumps for $70. just one of these pumps goes for around $80. your getting two additional pumps for what it cost for the price of one. these work like the day i got them and are mint. come get these and setup a bulletproof dosing system. you be happy you did. no more 2 part manual dosing. first come for these as this is an amazing deal. thanks.