Long lived sleptons, whose experimental signature is a charged track throughout the detector, are predicted in gauge mediation supersymmetric extensions of the standard model. In contrast to methods developed in the past which relied on identifying sleptons through their slow velocities, the technique introduced in this work assumes the majority of slepton are created in the decay chain \chi^0 \to \tilde e e. At a TeV scale LHC, sleptons need not be slow so their experimental signature is indistinguishable from that of muons. In our technique, using an appropriate set of kinematic cuts, we construct the opposite charge e-\mu invariant mass distribution with a sample mass given to the slepton (muon) candidate. Scanning over a range of sample masses, we locate the true slepton mass by its correspondence to the distribution with the highest peak (at the true neutralino mass).