Custom Silicone Sleeves for 3DMEUpgrade to custom fit! Our comfortable soft silicone sleeves convert your 3DME ambient IEMs from universal fit to custom fit, providing greater isolation, comfort, and fit security. Sensaphonics has designed these low profile IEM sleeves to be nearly invisible. After we receive your ear impressions, your custom fit sleeves are then handcrafted in our lab. Two weeks manufacturing time is typical.