diff --git a/bootloader/Makefile b/bootloader/Makefile
index 4a3209618..519a847cd 100644
--- a/bootloader/Makefile
+++ b/bootloader/Makefile
@@ -8,6 +8,7 @@ bootloader_src += $(addprefix bootloader/,\
   interface.cpp \
   jump_to_firmware.s \
   trampoline.cpp \
+  usb_desc.cpp \
 )
 
 bootloader_images = $(addprefix bootloader/, \
@@ -15,6 +16,6 @@ bootloader_images = $(addprefix bootloader/, \
   computer.png \
 )
 
-bootloader_src += $(ion_src) $(kandinsky_src) $(liba_src) $(libaxx_src) $(bootloader_images)
+bootloader_src += $(filter-out ion/src/device/shared/drivers/usb_desc.cpp,$(ion_src)) $(kandinsky_src) $(liba_src) $(libaxx_src) $(bootloader_images)
 
 $(eval $(call depends_on_image,bootloader/interface.cpp,$(bootloader_images)))
diff --git a/bootloader/usb_desc.cpp b/bootloader/usb_desc.cpp
new file mode 100644
index 000000000..be4930600
--- /dev/null
+++ b/bootloader/usb_desc.cpp
@@ -0,0 +1,12 @@
+
+namespace Ion {
+namespace Device {
+namespace USB {
+
+const char* stringDescriptor() {
+  return "@Flash/0x90000000/08*004Kg,01*032Kg,63*064Kg,64*064Kg";
+}
+
+}
+}
+}
diff --git a/ion/src/device/shared/drivers/Makefile b/ion/src/device/shared/drivers/Makefile
index 2db043c5f..67bfb6ff5 100644
--- a/ion/src/device/shared/drivers/Makefile
+++ b/ion/src/device/shared/drivers/Makefile
@@ -25,5 +25,6 @@ ion_device_src += $(addprefix ion/src/device/shared/drivers/, \
   swd.cpp \
   timing.cpp \
   usb.cpp \
+  usb_desc.cpp \
   wakeup.cpp \
 )
diff --git a/ion/src/device/shared/drivers/usb.h b/ion/src/device/shared/drivers/usb.h
index df27513e7..598aa4e9f 100644
--- a/ion/src/device/shared/drivers/usb.h
+++ b/ion/src/device/shared/drivers/usb.h
@@ -12,6 +12,7 @@ void initGPIO();
 void shutdownGPIO();
 void initOTG();
 void shutdownOTG();
+const char* stringDescriptor();
 
 }
 }
diff --git a/ion/src/device/shared/drivers/usb_desc.cpp b/ion/src/device/shared/drivers/usb_desc.cpp
new file mode 100644
index 000000000..34ea8527a
--- /dev/null
+++ b/ion/src/device/shared/drivers/usb_desc.cpp
@@ -0,0 +1,15 @@
+#include "usb.h"
+#include <ion/usb.h>
+#include <drivers/config/usb.h>
+
+namespace Ion {
+namespace Device {
+namespace USB {
+
+const char* stringDescriptor() {
+  return Config::InterfaceStringDescriptor;
+}
+
+}
+}
+}
\ No newline at end of file
diff --git a/ion/src/device/shared/usb/Makefile b/ion/src/device/shared/usb/Makefile
index a79991d74..02e931b6a 100644
--- a/ion/src/device/shared/usb/Makefile
+++ b/ion/src/device/shared/usb/Makefile
@@ -66,6 +66,7 @@ ion_device_dfu_src += $(addprefix ion/src/device/shared/drivers/, \
   swd.cpp \
   timing.cpp \
   usb.cpp \
+  usb_desc.cpp \
   wakeup.cpp \
 )
 
diff --git a/ion/src/device/shared/usb/calculator.h b/ion/src/device/shared/usb/calculator.h
index cf083860c..e5eaba3a4 100644
--- a/ion/src/device/shared/usb/calculator.h
+++ b/ion/src/device/shared/usb/calculator.h
@@ -3,6 +3,7 @@
 
 #include <stddef.h>
 #include <assert.h>
+#include <drivers/usb.h>
 #include <drivers/config/usb.h>
 #include "dfu_interface.h"
 #include "stack/device.h"
@@ -94,7 +95,7 @@ public:
     m_manufacturerStringDescriptor("NumWorks"),
     m_productStringDescriptor("NumWorks Calculator"),
     m_serialNumberStringDescriptor(serialNumber),
-    m_interfaceStringDescriptor(Config::InterfaceStringDescriptor),
+    m_interfaceStringDescriptor(stringDescriptor()),
     //m_interfaceStringDescriptor("@SRAM/0x20000000/01*256Ke"),
     /* Switch to this descriptor to use dfu-util to write in the SRAM.
      * FIXME Should be an alternate Interface. */