CREATE TABLE table_13555999_1 (specification VARCHAR, senior_high_school__15_18_yrs_ VARCHAR)

What is the specification where senior high school is 25mm?
SELECT specification FROM table_13555999_1 WHERE senior_high_school__15_18_yrs_ = "25mm"
SELECT "specification" FROM "table_13555999_1" WHERE "25mm" = "senior_high_school__15_18_yrs_"