• Small Black Berkey Rubber plugs for blocking unused filter holes in the upper chamber on all Berkey systems
• Large White Berkey Blocking plugs fits in all systems too
• All Berkey systems come standard with the proper amount and size of blocking plugs.  In case of loss or damage, replacement plugs may be purchased individually. 
• Both sizes are made of 100% safe BPA free non toxic material.
• XRP-LG may be used with Berkey stainless steel systems 
• In each pack is a set of 2 blocking Plugs  (for 1 Berkey system)