Definitely a magazine plug for a 3" Rem 870. The little screw aligned with a hole in the mag tube to hold the weight in place.
3 " and 2 3/4 "
From others. Items no longer being made. All of my 1100 and 870 28ga and 410 ga skeet guns have the second version
The first of these was what Remington called the “Vari-Weight” plug system that was offered for the 12-gauge shotgun only. This was a metal plug that weighed around ¾-pound and could be inserted into the magazine tube to increase the weight of the gun and move the balance point forward. The early Model 870s, particularly the standard grade AP models, were fairly light, listed at 6¾ pounds. It was not unusual to get a gun that weighed even a bit less, depending on the density of wood and the barrel length. This was great for upland hunters, who always look for a lighter gun. But, for waterfowlers and clay target shooters, the gun was too light. By adding the Vari-Weight plug, the gun’s weight increased considerably and made the gun more nose heavy at the same time, an important feature for both these sportsmen. But Remington quietly dropped the Vari-Weight plug offering, which had come standard with all 12-gauges, in the 1960s, about the time the standard AP model was dropped.
A modified form of the old Vari-Weight plug was revived for the smallbore 28-gauges and .410-bores, when Remington came out with its scaled-frame guns, in 1969. They were first offered as a matched pair of skeet guns and had weights that would attach to the magazine cap to increase forward weight. In actuality, this system had been available much earlier, when Remington introduced its small-framed Model 11-48 autoloader in 28-gauge and .410-bore. When the small-framed 870s came out, Remington simply adopted the same system to the new pump guns. However, as it had been with the 12-gauge, this practice was also stopped after a while.
