Aluminum Battery Boxes come in sealed, non-sealed versions.
Amazon.com: A.A Vented Battery Box for RV, Camper, Marine, Boat with Foam Strip Vapor Barrier (Top Vent) : Automotive
MTS Products® 250 - Vented Battery Box for Group 27 Batteries - CAMPERiD.com
Vented Battery Box Large White - $39.99
Battery Box Vent Kit | Battery Mart
Summit racing Sealed, exterior vent tube Battery box installed on Henry Kreismer's Subaru Impreza on Wheelwell
QuickCable - QuickCable Group 24 Polished Aluminum Battery Box
Battery Box Cooling and Venting - Is This Safe? — northernarizona-windandsun
Battery Box Complete W/Vent Black or White - GoIceFish
Battery Box, Blue, 10 1/2 in. deep, 13 in. wide, 9 1/2 in. tall, by Moroso
Camco 55370 Vented RV/Marine Battery Box, Double Side-by-Side - Protects Your RV or Marine Battery from Collisions and Contaminants - Holds (2) Group 24 Batteries, Black