What color is model # pd-kb400w?
CREATE TABLE "features_by_model" (
  "model_name" text,
  "model_num" text,
  "color" text,
  "switch_type" text,
  "interface" text,
  "blank_keytops" text,
  "introduced" text
);
SELECT "color" FROM "features_by_model" WHERE "model_num"='pd-kb400w';