diff --git a/src/fat/fat12.c b/src/fat/fat12.c
index c1c7efa..529f245 100644
--- a/src/fat/fat12.c
+++ b/src/fat/fat12.c
@@ -121,12 +121,12 @@ int fat12_allocclusters(image* img, bpb16* bpb, int cluster_count) {
         if (!cluster) {
             if (prev_al_clus) {
                 if (prev_al_clus % 2) {
-                    fat_start[prev_al_clus/2].odd_clust1 = (char)(i&0xF);
-                    fat_start[prev_al_clus/2].odd_clust2 = (char)(i>>8);
+                    fat_start[prev_al_clus/2].odd_clust1 = (char)(i&0x00F);
+                    fat_start[prev_al_clus/2].odd_clust2 = (char)(i>>4);
                 }
                 else {
                     fat_start[prev_al_clus/2].even_clust1 = (char)i;
-                    fat_start[prev_al_clus/2].even_clust2 = (char)((i>>8)&0xF);
+                    fat_start[prev_al_clus/2].even_clust2 = (char)((i>>8)&0x0F);
                 }
             } 
             prev_al_clus = i;
@@ -184,7 +184,7 @@ void fat12_write_file_via_cluster_chain(char* data, size_t data_size,
         int nclus = 0;
         if (clustern%2) {
             nclus |= (fat[clustern/2].odd_clust1 & 0xF);
-            nclus |= fat[clustern/2].odd_clust2 << 8;
+            nclus |= fat[clustern/2].odd_clust2 << 4;
         } else {
             nclus |= fat[clustern/2].even_clust1;
             nclus |= fat[clustern/2].even_clust2 << 8 ;
diff --git a/src/main.c b/src/main.c
index 37a6125..3794061 100644
--- a/src/main.c
+++ b/src/main.c
@@ -94,7 +94,6 @@ void mode_add(mkimg_args* args) {
 }
 
 int main(int argc, char* argv[]) {
-    printf("%u\n",sizeof(bpb16));
     mkimg_args* args = arg_parse(argc, argv);
     switch (args->mode) {
         case create: