This model contains the Heil Ic element.
The newly designed HMM brings new technology to the hand microphone. No question when you place a microphone element inside a clam shell. The result is a hollow muffled sound but Amateur Radio operators have lived with it for decades.
To solve this problem, we installed a grill on the top of the microphone that detunes the internal resonance of the housing. We came up with a very special full range microphone element with great speech articulation.
The result is a phenomenal hand microphone. A very flexible but sturdy coil cable terminates as all of our headsets with 1/8” male for the microphone and a ¼” male for the PTT control. The microphone is compatible with the AD-1 series of adapters.
This definitely raises the bar for all hand microphones. The new Heil HMM.