diff --git a/src/mame/drivers/sbrain.cpp b/src/mame/drivers/sbrain.cpp
index 0482f813a28..b197ddea568 100644
--- a/src/mame/drivers/sbrain.cpp
+++ b/src/mame/drivers/sbrain.cpp
@@ -754,7 +754,7 @@ ROM_START( sbrain )
 	ROMX_LOAD("3_1.z69", 0x0000, 0x0800, CRC(b6a2e6a5) SHA1(a646faaecb9ac45ee1a42764628e8971524d5c13), ROM_BIOS(2))
 	ROM_SYSTEM_BIOS( 3, "3_05", "3.05" )
 	ROMX_LOAD("qd_3_05.z69", 0x0000, 0x0800, CRC(aedbe777) SHA1(9ee9ca3f05e11ceb80896f06c3a3ae352db214dc), ROM_BIOS(3))
-	ROM_SYSTEM_BIOS( 4, "4_2_50", "4.2 50Hz")
+	ROM_SYSTEM_BIOS( 4, "4_2_50", "4.2 (50Hz hack)")
 	ROMX_LOAD("sbii_sb4_2_50hz.z69", 0x0000, 0x0800, CRC(285a894b) SHA1(694fef446fe19c0962f79951aa4d464489a9d161), ROM_BIOS(4))
 	// Using the chargen from 'c10' for now.
 	ROM_REGION( 0x2000, "chargen", 0 )