JAYO Dual Color Matte PLA 3D Printer Filament, Black-Red Two-Tone PLA, Matte Finish Hides Layer Lines, ± Accuracy, 1.1kg (2.42 lbs) Spool, Fit Most FDM Printers

Multi-pack bundles are the point — buying 4 or 10 spools at once brings the per-kg cost down sharply compared to individual purchases. Good for anyone running the same color through a lot of prints and watching their material budget.