Check the listing for details. Bluelab pH Probe Replacement -meter combo guardian calibration blue lab. Condition: New. Listed at 71.99 USD. --> Brand New! Bluelab pH Probe Replacement About the product Easy to clean because of its bullet shaped glass bulb. Fully waterproof and less fragile than all-glass electrodes because of its tough polypropylene barrel. Gel filled (non-refillable) making it maintenance free and a double junction reference providing longer life! What's in the Package Additional Images - Bluelab pH Probe Replacement FIVE-STAR SATISFACTION GUARANTEED --> Our company has a reputation for delivering excellent service, ensuring buyers' privacy, and delivering quality products at reasonable, competitive prices. We strive to earn a 5-star rating from every transaction. If you are satisfied with the product and service you receive, please take a moment to leave us positive seller feedback. In turn, we will also provide 5-star buyer feedback when your order leaves our facility. If by chance there was something unsatisfactory about your experience, please contact us, and we'll do what's necessary to remedy the problem and ensure 100% satisfaction! TERMS, CONDITIONS, WARRANTIES & POLICIES ABOUT THE HYDRO STORE