This is for 1 piece, usually you will requie a pair so ensure you choose a quantity of 2 if that is the case.
Blocking plug to block any unused filter holes in the upper chamber of all stainless steel Berkey systems
Fits all stainless steel Berkey systems including the Go Berkey, Travel Berkey,  Big Berkey,  Royal Berkey,  Imperial Berkey, Crown Berkey, and British Berkefeld models
All stainless steel systems come standard with the proper amount of blocking plugs; in case of loss or damage, plugs may be purchased individually
Blocking plug comes with wingnut and 2 washers
Not recommended for the Berkey Light system
Single plug