Dan, most SLAs do not care about which side they are lying on. Try to get the manufacturer's recommendations. If in doubt do not put on side or upside down. For short periods of time nothing will happen but in time condensation and other effects may remove the electrolyte from the porous membrane and make a liquid pool on something that will corrode. Not to mention the reduction in capacity and the fact that the liquid pool will cause liquid acid to seep out through the valve seal when the battery is next heated by use or charging. Peter -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu