Those are all fields available from the tables in the report builder's default query.
SELECT Top 1000000
tblAssets.AssetID,
tblAssets.AssetName,
tsysAssetTypes.AssetTypename,
tsysAssetTypes.AssetTypeIcon10 As icon,
tblAssets.IPAddress,
tblAssets.Lastseen,
tblAssets.Lasttried,
tblAssetCustom.Manufacturer,
tblAssetCustom.Model,
tblAssetCustom.Serialnumber
FROM
tblAssets
INNER JOIN tblAssetCustom ON tblAssets.AssetID = tblAssetCustom.AssetID
INNER JOIN tsysAssetTypes ON tsysAssetTypes.AssetType = tblAssets.Assettype
WHERE
tblAssetCustom.State = 1
ORDER BY
tsysAssetTypes.AssetTypename,
tblAssetCustom.Manufacturer,
tblAssetCustom.Model,
tblAssetCustom.Serialnumber