The mp_skins_sas_trench.zip file you have requested: Skins / Allies / SaS Trench Skins - 4.74mb is not available. Perhaps try browsing all files for the game Return To Castle Wolfenstein and upload any files you want to share or are missing. This is the only information we could locate:
Alternate Allies Skins. Includes new body, legs and helmets. This pak includes individual skins for each class.