After pushing an entire bag of this
into the opening and then spraying in this
and then shoving in half a bat of this
my brother was finished....confident the mice could no longer get in and no more cold air in my kitchen!
Alas, apparently a mouse or two was hidden somewhere in the kitchen. I know because Gracie brought one up to me in the studio as a gift. Thankfully, her latest "giftie" was intact and just dead. (I sent Grace back to the kitchen to search for more!)