diff --git a/src/mame/drivers/pse.cpp b/src/mame/drivers/pse.cpp
index 206b5a849b8..40de26529d8 100644
--- a/src/mame/drivers/pse.cpp
+++ b/src/mame/drivers/pse.cpp
@@ -17,6 +17,7 @@
  Maneater (1975/11)              YES
  Play Five (1975?)               UNKNOWN
  Scandia (cabinet) (1975/08)     NO
+ Space Out (late 1970s)          UNKNOWN (most likely)
  Two Game (1974)                 UNKNOWN
  U.N. Command (1977)             YES?