If you have purchased a STEM in a Box kit prior to subscribing, unfortunately we have no way of catching this since the Club kits are run through a completely different database. If you let us know what STEM kits you purchased prior to your STEM Lab Deluxe kits shipping, we will make sure you do not receive any repeat kits.
There may also be some repeat experiments between STEM Lab and STEM Lab Deluxe. If you have been a STEM Lab Deluxe customer for several months, we would recommend you do not join the STEM Lab. There should not be much duplication between with STEM Snack and the other Clubs.