CREATE TABLE table_name_95 (entrant VARCHAR(255), points VARCHAR(255), chassis VARCHAR(255), engine VARCHAR(255), year VARCHAR(255))
What kind of Entrant has a Maserati Straight-6 Engine, built in the year 1958 or early, and has a Maserati 250f Chassis with points less than 4?
    
SQL: SELECT entrant FROM table_name_95 WHERE engine = "maserati straight-6" AND year < 1958 AND chassis = "maserati 250f" AND points < 4