I've since looked it up. It shows up in the parts sections for the 32/33 printer and the TD base for the 35ASR. 

Seems like I saw some stand alone device that would have used it too, ah yes a LABD, 28/35 answer back unit, section 574-235-800.

I doubt anyone has one of those in the 28 version.

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You said "tomorrow" yesterday.

The above comments or recommendations are SWAG. Use at your own risk.
John, W9DDD
On 3/22/2023 5:43 PM, WAYNE wrote:
John,

I dont think it fits 28 equipment.� I know it doesnt fit 15's.��

If nobody�wants it I would like it.��

73,

Wayne
KB1FDW