VMAXTANKS MR86-50 50ah AGM Hi Performance Battery for High Degree Easy Jet Mc101a Navigator Mc501r Robot Jet Mc101r and 18-50LB Minn Kota Cobra Sevylor and Other Trolling Motors 7.8"*6.8"*6.7"H Heavy Duty 12V AGM DEEP CYCLE BATTERY with Float Service Life span of 8 to 10 years. Electrolyte Suspension system VMAX tanks utilize an electrolyte suspension system consisting AGM (Absorbed Glass Matt) of a high porosity that totally absorb and contain the electrolyte. No silica gels or any other contaminants are used Heavy Duty Grids: VMAX heavy duty lead tin alloys provide an extra margin of performance and service life in either float or cyclic applications, even after repeated over discharges. Maintenance Free Operation: There is no need to check specific gravity of the electrolyte or add water to VMAX tanks during float service life. In fact, there is no provision for this type of maintenance. Exclusive Authorized Amazon Seller : bargainshore