Phil;
It looks like the
http://rollsbattery.com/public/specsheets/12FS125.pdf is a wet. In addition to the caps in the illustration, the specs also say that there is 1.5" of electrolyte reserve above the plates. The only way this reserve can be above the plates is in an upright-only orientation. This reserve is the clincher because AGMs can be placed on a side or end and they are spillproof. The battery is listed under MOTIVE POWER.
Here is how I find the AGMs.
Click
http://rollsbattery.com/,
hover mouse over PRODUCTS,
click AGM,
click 12 VOLT,
click 12Volt (Sealed 6 cell),
select an AGM battery.
HTH;
John