Here is another Yamazaki Lunch Pack, called the fried fish and tartar sauce sandwich and the package stresses that the tartar sauce contains pickles. This is the new flavor of the month requested by customers in an online poll. I cannot find exactly what type of fish is used, but it appears to be mimicking fast food fish sandwiches. McDonald's has used cod, hoki and pollack over the years. ヤマザキ ランチパック フィッシュフライ&タルタルソース
http://www.yamazakipan.co.jp
Photo is a web capture for explanatory purposes, copyright belongs to the company.