A Rain Bird sprinkler system controller from the 1980s. Cannot verify that it would work for purpose these days, but can verify that it has several fun and tactile dials to play with inside! Set your kiddos* up in front of this, they'll be occupied for hours and probably grow up to be engineers!

(*For legals reasons I must tell you to supervise children near anything containing small parts, even though it doesn't seem like anything in this unit is removable.)