This Harrington & Richardson manufactured first variation outside magazine tube assembly is for the model 852 Fieldsman bolt action rimfire rifle and is in very good condition with light wear.  The first variation has a metal transition collar that is .50 " in diameter where the 2 pieces connect. (file photo)

Note: Harrington & Richardson model 852 Fieldsman bolt action rimfire rifles with the following serial numbers have been observed with this part: NSN