CREATE TABLE table_38006 ("Unit" TEXT, "Russian" TEXT, "Ratio" TEXT, "Metric value" TEXT, "Avoirdupois value" TEXT)

What Russian has an Avoirdupois value of 0.686 gr?
SELECT "Russian" FROM table_38006 WHERE "Avoirdupois value" = '0.686 gr'
SELECT "Russian" FROM "table_38006" WHERE "Avoirdupois value" = '0.686 gr'