This is a read-only integer, in dB up to 200, reporting the current Echo Return Loss for the call leg, functioning as a wider-range revision of the original ERL-level object which topped out at 45 dB, with -1 again meaning undetermined or disabled. An admin uses this revised object on gateways or DSPs capable of reporting a broader ERL range, getting more precise echo-suppression data than the original object could represent. For example, on newer hardware capable of very high ERL values, an admin would prefer reading this Rev1 object over the original to avoid the older object's value simply capping out at 45 dB.