bulksupplements L-Carnitine L-Tartrate (LCLT) - Burn fat w/ L-Carnitine What Is L-Carnitine L-Tartrate (LCLT)? L-carnitine L-tartrate, also commonly referred to as LCLT, is a combination of carnitine and tartaric acid that is easier to absorb and is commonly added to energy drinks and pre-workout regimens. L-carnitine is a compound derived from an amino acid that is involved in metabolism in most mammals and plants. L-carnitine is produced naturally by the body and exists in two biologically active isomers, L-carnitine and D-carnitine, which have drastically different effects on the body. L-carnitine (not to be confused with D-carnitine) is sometimes referred to as simply "carnitine.