A pipette rack assembly, comprising: (a) a pipette tip tray, the pipette tip tray comprising: (i) an uppermost surface of the tray defining a first plane; (ii) a lower surface of the tray defining a second plane; (iii) a deck located between the first and second planes; (iv) a plurality of shaft apertures, each of the plurality of shaft apertures extending through the deck and having a size or shape configured to receive a shaft of a pipette tip and reduce movement of the pipette tip relative to the tray; (v) at least one locking element operable to be biased and released, the at least one locking element comprising a hook operably coupled to the tray and extending below the second plane; and (b) a rack comprising (i) a surface configured to receive the pipette tip tray; (ii) at least one sidewall extending downwardly from the surface; and (iii) at least one receiving element on the surface of the rack and vertically aligned with the at least one locking element of the pipette tip tray when the pipette tip tray is positioned over the rack, wherein the at least one locking element is configured to be coupled to the at least one receiving element to secure the pipette tip tray to the rack, characterized in that: the hook is located beneath the deck and below the second plane. (a) a pipette tip tray, the pipette tip tray comprising: (i) an uppermost surface of the tray defining a first plane; (ii) a lower surface of the tray defining a second plane; (iii) a deck located between the first and second planes; (iv) a plurality of shaft apertures, each of the plurality of shaft apertures extending through the deck and having a size or shape configured to receive a shaft of a pipette tip and reduce movement of the pipette tip relative to the tray; (v) at least one locking element operable to be biased and released, the at least one locking element comprising a hook operably coupled to the tray and extending below the second plane; and (i) an uppermost surface of the tray defining a first plane; (ii) a lower surface of the tray defining a second plane; (iii) a deck located between the first and second planes; (iv) a plurality of shaft apertures, each of the plurality of shaft apertures extending through the deck and having a size or shape configured to receive a shaft of a pipette tip and reduce movement of the pipette tip relative to the tray; (v) at least one locking element operable to be biased and released, the at least one locking element comprising a hook operably coupled to the tray and extending below the second plane; and (b) a rack comprising (i) a surface configured to receive the pipette tip tray; (ii) at least one sidewall extending downwardly from the surface; and (iii) at least one receiving element on the surface of the rack and vertically aligned with the at least one locking element of the pipette tip tray when the pipette tip tray is positioned over the rack, (i) a surface configured to receive the pipette tip tray; (ii) at least one sidewall extending downwardly from the surface; and (iii) at least one receiving element on the surface of the rack and vertically aligned with the at least one locking element of the pipette tip tray when the pipette tip tray is positioned over the rack, the hook is located beneath the deck and below the second plane.