diff --git a/libsession/src/main/java/org/session/libsession/messaging/messages/control/ClosedGroupUpdate.kt b/libsession/src/main/java/org/session/libsession/messaging/messages/control/ClosedGroupUpdate.kt
index 9b0ba71cf6..f72c8a1dce 100644
--- a/libsession/src/main/java/org/session/libsession/messaging/messages/control/ClosedGroupUpdate.kt
+++ b/libsession/src/main/java/org/session/libsession/messaging/messages/control/ClosedGroupUpdate.kt
@@ -141,7 +141,7 @@ class ClosedGroupUpdate() : ControlMessage() {
 
 // extension functions to class ClosedGroupSenderKey
 
-private fun ClosedGroupSenderKey.Companion.fromProto(proto: SignalServiceProtos.ClosedGroupUpdate.SenderKey): org.session.libsignal.service.loki.protocol.closedgroups.ClosedGroupSenderKey {
+private fun ClosedGroupSenderKey.Companion.fromProto(proto: SignalServiceProtos.ClosedGroupUpdate.SenderKey): ClosedGroupSenderKey {
     return ClosedGroupSenderKey(chainKey = proto.chainKey.toByteArray(), keyIndex = proto.keyIndex, publicKey = proto.publicKey.toByteArray())
 }
 
diff --git a/libsession/src/main/java/org/session/libsession/messaging/messages/visible/Attachment.kt b/libsession/src/main/java/org/session/libsession/messaging/messages/visible/Attachment.kt
new file mode 100644
index 0000000000..3e1530f34e
--- /dev/null
+++ b/libsession/src/main/java/org/session/libsession/messaging/messages/visible/Attachment.kt
@@ -0,0 +1,71 @@
+package org.session.libsession.messaging.messages.visible
+
+import android.util.Size
+import android.webkit.MimeTypeMap
+import org.session.libsignal.service.internal.push.SignalServiceProtos
+import java.io.File
+import java.net.URL
+import kotlin.math.absoluteValue
+
+class Attachment : VisibleMessage<SignalServiceProtos.AttachmentPointer?>() {
+
+    var fileName: String? = null
+    var contentType: String? = null
+    var key: ByteArray? = null
+    var digest: ByteArray? = null
+    var kind: Kind? = null
+    var caption: String? = null
+    var size: Size? = null
+    var sizeInBytes: Int? = 0
+    var url: String? = null
+
+    companion object {
+        fun fromProto(proto: SignalServiceProtos.AttachmentPointer): Attachment? {
+            val result = Attachment()
+            result.fileName = proto.fileName
+            fun inferContentType(): String {
+                val fileName = result.fileName ?: return "application/octet-stream" //TODO find equivalent to OWSMimeTypeApplicationOctetStream
+                val fileExtension = File(fileName).extension
+                val mimeTypeMap = MimeTypeMap.getSingleton()
+                return mimeTypeMap.getMimeTypeFromExtension(fileExtension) ?: "application/octet-stream" //TODO check that it's correct
+            }
+            result.contentType = proto.contentType ?: inferContentType()
+            result.key = proto.key.toByteArray()
+            result.digest = proto.digest.toByteArray()
+            val kind: Kind
+            if (proto.hasFlags() && (proto.flags and SignalServiceProtos.AttachmentPointer.Flags.VOICE_MESSAGE_VALUE) > 0) {
+                kind = Kind.VOICEMESSAGE
+            } else {
+                kind = Kind.GENERIC
+            }
+            result.kind = kind
+            result.caption = if (proto.hasCaption()) proto.caption else null
+            val size: Size
+            if (proto.hasWidth() && proto.width > 0 && proto.hasHeight() && proto.height > 0) {
+                size = Size(proto.width, proto.height)
+            } else {
+                size = Size(0,0) //TODO check that it's equivalent to swift: CGSize.zero
+            }
+            result.size = size
+            result.sizeInBytes = if (proto.size > 0) proto.size else null
+            result. url = proto.url
+            return result
+        }
+    }
+
+    enum class Kind {
+        VOICEMESSAGE,
+        GENERIC
+    }
+
+    // validation
+    override fun isValid(): Boolean {
+        if (!super.isValid()) return false
+        // key and digest can be nil for open group attachments
+        return (contentType != null && kind != null && size != null && sizeInBytes != null && url != null)
+    }
+
+    override fun toProto(transaction: String): SignalServiceProtos.AttachmentPointer? {
+        TODO("Not implemented")
+    }
+}
\ No newline at end of file
diff --git a/libsession/src/main/java/org/session/libsession/messaging/messages/visible/attachments/Attachment.kt b/libsession/src/main/java/org/session/libsession/messaging/messages/visible/attachments/Attachment.kt
deleted file mode 100644
index f50ffb6baa..0000000000
--- a/libsession/src/main/java/org/session/libsession/messaging/messages/visible/attachments/Attachment.kt
+++ /dev/null
@@ -1,17 +0,0 @@
-package org.session.libsession.messaging.messages.visible.attachments
-
-import org.session.libsession.messaging.messages.visible.BaseVisibleMessage
-import org.session.libsignal.service.internal.push.SignalServiceProtos
-
-internal class Attachment : BaseVisibleMessage() {
-
-    companion object {
-        fun fromProto(proto: SignalServiceProtos.Content): Attachment? {
-            TODO("Not yet implemented")
-        }
-    }
-
-    override fun toProto(): SignalServiceProtos.Content? {
-        TODO("Not yet implemented")
-    }
-}
\ No newline at end of file