Mighty Max Battery YTX20L-BS 12V 18Ah Motorcycle Battery — 270 CCA AGM Sealed, Maintenance-Free

The Mighty Max Battery YTX20L-BS is a sealed 12V, 18AH AGM motorcycle battery delivering 270 CCA in a maintenance-free, ready-to-install package.

This compact sealed lead-acid (SLA) battery uses absorbed glass mat (AGM) construction to provide reliable starting power and steady electrical performance for motorcycles, ATVs, personal watercraft, and snowmobiles. It ships fully charged, sealed against leaks, and does not require watering or routine maintenance. Designed for vibration resistance and versatile mounting, it’s a practical upgrade or replacement battery for a wide range of powersports machines.

How much starting power and capacity does this battery provide?

The YTX20L-BS supplies 12 volts with an 18 amp-hour (AH) capacity and 270 cold cranking amps (CCA), suitable for most medium-displacement motorcycles and many ATVs and personal watercraft. These ratings translate to dependable starts, even in cooler conditions, and enough reserve capacity to support accessories for short periods.

• Voltage: 12V nominal
• Capacity: 18 AH for sustained electrical support
• Starting power: 270 CCA for reliable engine starts
• Sealed AGM design for leak-free operation

What are the physical size and terminal details I need to know?

The battery measures approximately 6.88 inches long, 3.50 inches wide, and 6.13 inches tall. Terminal polarity is negative on the left and positive on the right when oriented for normal installation, and the package includes the battery and mounting screws only.

• Dimensions: 6.88" x 3.50" x 6.13" (L x W x H)
• Polarity: Negative left, Positive right
• Included: Battery and screws; no harnesses or mounts
• Mounting: Can be installed in multiple orientations

How durable and maintenance-free is the AGM construction?

AGM technology traps electrolyte in glass mats, creating a spill-proof, sealed battery that resists vibration and can be mounted in various positions. Because it’s sealed and rechargeable, you won’t need to add water or perform routine electrolyte checks—ideal for seasonal vehicles or machines used in wet or rough conditions.

• Absorbed Glass Mat (AGM) — sealed and leak-resistant
• Rechargeable and maintenance-free—no watering
• Vibration and shock-resistant for powersports use
• Weatherproof performance in rain, snow, and heat

What installation and warranty support do I get?

Installation is straightforward: remove the old battery, verify terminal orientation, secure the YTX20L-BS with the included screws, and connect the cables. The battery comes charged and ready to install, and it’s backed by a full one-year warranty for peace of mind against manufacturing defects.

• Ships fully charged and ready to install
• Simple swap with matching terminal layout
• One-year warranty for defects
• No special tools required beyond basic hand tools

Who this is for: The Mighty Max Battery YTX20L-BS fits riders and owners who need a compact, maintenance-free battery with solid starting power and reliable accessory support. It’s a good choice for motorcycle and ATV owners, PWC and jet ski users, snowmobile operators, and anyone who wants a sealed AGM battery that tolerates vibration, varied mounting positions, and seasonal storage without frequent upkeep.