One of many modified by Father Elijah, this was used collar to force an unfortunate wastelander to purchase a rangefinder from Sarah Weintraub. Once he had acquired what he was tasked to purchase, the man tried to remove the collar himself. He inquired about someplace with concrete walls that was free to stay, Sarah referred him to the ruined building outside Mick & Ralph's in Freeside. This where, judging by the decapitated body and the wrench near the body, he attempted to disarm it and detonated it in the process. Oddy, the collar, despite detonating, is still intact.
The collar has zero DT, and no in-game effect except for being visible as a bulky metallic collar on your character if worn.
↑The Courier: "I'm looking for an antique rangefinder somebody might've sold you." Sarah Weintraub: "I sold it to a man not too long ago. Real twitchy, nervous sort of guy. Kinda seemed like he was wiggin' out about something. Had a funny collar on. I wanted to ask him about it but I figured maybe I'd regret asking. People are weird around here." The Courier: "What kind of collar?" Sarah Weintraub: "Well it was metal, and kind of thick. At first I thought he'd come from Gomorrah, but they're more into leather there Didn't look comfortable. He kept reaching up like he was gonna itch it, but he always stopped himself." (Sarah Weintraub's dialogue)
↑The Courier: "Did you happen to find out where he was from?" Sarah Weintraub: "No, but I know where he was going. He asked me if I knew of any place where he could hide out for a while. Wanted somewhere with concrete walls. Something about airwaves. I forget. But I guess he spent all his money on the rangefinder, because he said it had to be somewhere free to stay." The Courier: "What'd you tell him?" Sarah Weintraub: "I said I didn't know about anything like that around here. But if he wanted to live for free, a lot of people do that in Freeside. I know there's a concrete building there across from Mick and Ralph's. No ceiling, but I think it still counts. Went up there one time to try and... you know... meet my neighbors in the biz. But you know, I don't think they took me very seriously." (Sarah Weintraub's dialogue)