Protective Iron Plate on the Heart in order for Luck to Never Leave Your at the Front

Essential souvenir for any Imperial Japanese army serviceman.

Well-polished so that it can be used as a mirror.

Engraved

武運長久祈- Praying for Continuing/Long-lasting Fortune in Warfare; Continued Luck in the Fortunes of War; [May] Unchanging Luck Always Accompany the War

Original case.

心臓- Heart

防護板- Protective Plate

and under the flag is the familiar

武運長久祈- Praying for Continuing/Long-lasting Fortune in Warfare; Continued Luck in the Fortunes of War; [May] Unchanging Luck Always Accompany the War

戦塵を洗ったご自分の健康美を映す事ができます。- You can see your own health and beauty after washing the dust of war.

左ポケットへ入レテ下サイ」とある。- Put it in your left pocket.

 

Another example.
Size 105 × 85 mm.

大阪十三テラス製作所製品 - Product of Osaka Juso Terrace Manufacturing Co., Ltd.

 

Additional examples made by the same manufacturer.

 

Variation.

 

Different type. Concave unpolished plates.

軍中用品 - Military Supplies/Goods

心臙保護鈑 - Heart Protection Plate

特別強い鋼製 - Made of Extra Strong Steel

 

And don't forget to take a sip of

豊太閤ウヰスキ - Toyotako Whiskey

for

武運長久祈- Continued Luck in the Fortunes of War