If your Toshiba Satellite C855 is feeling sluggish and struggling with multiple tabs or programs, this A-Tech 8GB DDR3 RAM upgrade might be exactly what it needs to get moving again! This is a single 8GB stick running at 1600MHz (PC3-12800) that's specifically designed to work with various C855 models including C855-15U, C855-18D, C855-18U, C855-18V, C855-18Z, C855-190, C855-19X, C855-1H8, C855-1J2, C855-1JG, C855-1JN, and several others. It's non-ECC memory, which is standard for most consumer laptops, and the SO-DIMM form factor means it'll fit perfectly in your laptop's memory slot. Installation is pretty straightforward if you're comfortable opening up your laptop - just make sure to ground yourself first to avoid static damage. Once installed, you'll notice snappier performance, better multitasking capability, and fewer of those annoying slowdowns when you have multiple applications running. A-Tech is known for reliable memory products, and this one comes with a lifetime warranty for peace of mind. Perfect if you're running Windows 10 or 11 and finding that your current 4GB (or less) just isn't cutting it anymore. Just double-check your exact model number against the compatibility list to make sure it's the right fit. For the price, it's one of the most cost-effective ways to breathe new life into an older laptop that's still structurally sound but just needs a performance boost.