Yes, the Libre uses Optium strips. Been using the Optium ketone strips for years with the stand-alone Optium meter (as integrated into the Libre handset) and it also does BG readings. Strips are quite useful as they're individually wrapped and colour coded: blue for BG, lilac for BK. No rattling pot of strips to bug you, or empty over the floor when hands are cold - can slip a few into a wallet too if you're travelling light. Can't comment on BG accuracy against alternatives though as rarely used that function.