About 303 Slabs

303 Slabs is a Colorado-based football card shop and collector resource specializing in rare, professionally graded Jaxson Dart cards, premium New York Giants collectibles, true NFL Shield cards, one-of-ones, low-numbered parallels, rookie cards, and other investment-grade football cards.

Founded by collector Johnny Dianni, 303 Slabs grew from a personal passion for finding distinctive football cards into a business focused on quality, authenticity, transparency, and collector trust. Every card is selected from a collector’s perspective, with an emphasis on pieces that offer genuine rarity, strong visual appeal, and long-term significance within the hobby.

A Special Focus on Jaxson Dart Cards

Jaxson Dart cards are a central focus of the 303 Slabs collection. The site features an evolving selection of premium Dart rookie cards, including rare NFL Shield patches, one-of-one cards, low-numbered memorabilia cards, graded rookies, case hits, and other difficult-to-find New York Giants collectibles.

303 Slabs also documents notable Jaxson Dart cards and provides collector-focused information about card rarity, patch terminology, grading, product lines, and the differences between true NFL Shields and other shield-logo memorabilia patches.

Carefully Curated Graded Football Cards

In addition to Jaxson Dart, 303 Slabs offers professionally graded football cards featuring notable rookies, quarterbacks, New York Giants players, emerging NFL stars, rare parallels, premium patches, and one-of-one collectibles.

Cards are accurately described, securely packaged, and presented with clear images and grading information. Because many cards are exceptionally scarce, inventory changes frequently and some cards may remain visible after sale as part of the 303 Slabs collector archive.

Built by a Collector

303 Slabs is collector-owned and operated. That means every transaction is approached with the same care, communication, and attention to detail expected when purchasing an important card for a personal collection.

Collectors are welcome to contact Johnny with questions about available cards, offers, potential trades, Jaxson Dart cards, or football-card collecting in general.