ED1/ED2 Header O-Ring fitting-connection_Slip x Insert Meter identifies which probe is

Meter identifies which probe is in use and rettains calibrations

This is a genuine Zodiac replacement eyeball fitting

000 gallons of water monthly

One drop equals 10 parts per million (ppm) CI

ED1/ED2 Header O-Ring fitting-connection_Slip x Insert Meter identifies which probe isThis is a Hayward Header O Ring for H Series Induced Draft, Low NOx Induced Draft, Electronic ED2 Style, Millivolt Electronic ED1 Style Pool Heaters. This Header O Ring goes on the following models: H150, H200 H210 H250, H300 H350, H400 Millivolt Electronic Ignition Pool and Spa Hot Tub Heaters and H250IDL2, H350IDL2, H400IDL2 Pool and Spa Hot Tub Heaters.