Spiral wound element for separation

A spiral wound membrane element comprising layers of membrane material fluid tight sealed along three edges enclosing a permeate spacer creating at least one permeate envelope which is contacted along at least one membrane face with a feed-retentate spacer, the entire multi-layer arrangement being wound around a hollow central mandrel and with which the permeate envelope is in fluid communication through its fourth unsealed edge thereby creating a spiral wound element, wherein the feed-retentate spacer comprises at least one layer having an open cross-sectional area of at least 30 to 70% and wherein the permeate spacer comprises at least three layers characterized in that the outer layers of the three layers are a fine material having an open cross-sectional area of about 10 to 50% and a stiffness of at least 2-3.times.10.sup.5 lbs/sq. inch and a coarse layer having an open cross-sectional area of about 50 to 90% is interposed between the aforesaid fine outer layers and wherein the fine outer layers are in interface contact with the membrane layers enclosing the permeate spacer.