Hello, thank you for your question, You do need the measurements from inside the pump which means you do need to disassemble. However, sometimes you can get the measurements from the manufacturers part code. If you need any help with measurements, our team are happy to assist. Give the office a call 033 000 22 223 and ask for Gavin or technical.
Thank you for your comment, we are sorry that you have some concerns. A member of the Beaumanor management team will be in touch to discuss this with you as soon as possible