Equine Sperm Gradient Lower Layer 90%Equine Sperm Gradient Lower Layer 90% For semen preparation for IVF ICSI and to be used in combination with Stroebech Semen Wash Medium Description and Prod. No. 20 ml. Gradient Medium, Prod No. 2. 11. 020 The media are supplied sterile in 20 ml glass bottles for sperm separation by density gradient centrifugation. The medium is Hepes buffered and does not require CO2 equilibration The medium is ready to use and does not need any supplements Medium