(especially the "central" divisions) during World War II. Spain also received shipments of the helmet. During the inter-war years, several military missions were sent to South America under the command of Hans Kundt. After the Chaco War, the Bolivian army adopted the Stahlhelm and continued using it until recently. The exported M1935 helmets were similar to the German issue, except for a different liner. Some countries manufactured their own helmets using the M1935 design, and this basic design was in use in various nations as late as the 1970s. The Germans helped the Hungarians copy the M1935 design. The WWII M38 Hungarian steel helmet is nearly identical to the German M1935. Both have almost the same shape, riveted ventilation holes, and the classic rolled edge. Differences include somewhat rougher Hungarian finishing, a different liner and different rivets position – the split pins are situated behind the ventilation holes. A square metal bracket is riveted on the rear, above the back brim, to secure the helmet to the knapsack while marching. It was typically painted in Hungarian brown-green, though blue-grey versions existed. It is sometimes called the "Finnish M35" due to its extensive use by the Finnish Army during the Continuation War 1941–44. After World War I Poland seized large quantities of M1918 helmets. Most were later sold to various countries, including Spain. However, at the end of the 1930s, it was discovered that the standard Polish wz. 31 helmet was unsuitable for tank troops and motorized units; while offering decent protection, it was too large and heavy. As a stop-gap measure before a new helmet was developed, the General Staff decided to issue M1918 helmets to the 10th Motorized Cavalry Brigade, which used them during the September Campaign. During the time of the Warsaw Uprising the helmet was also worn by the members of the Polish Home Army and it was during this time that the helmet became the symbol of the resistance, as every Stahlhelm worn by a soldier of the underground army signified a dead German occupier it was taken from. In November 1926, the Irish Defence Forces adopted the Stahlhelm. As the Treaty of Versailles barred Germany from exporting steel helmets, the Irish turned to London-based Vickers, ordering 5,000 copies of a model closely resembling the M1918 helmet. The helmet remained in use until it was replaced by the British Mark II model in 1940. Following the