Neptune Systems has designed the MPR - Magnetic Probe Rack specifically for the Apex and will hold up to 4 probes with one hole being slightly over-sized to hold those larger probes like the Neptune temp probe. By simply placing the MPR in your sump or tank, you can now securely hold all your probes in a single spot. The Neptune MPR can work with glass up to 1/2" thick and keep all your probes secure and safe.
Dimensions: 4" long by 2.5" deep with the screws all the way backed out.