The Showgard 52x36mm (Size C) in Clear is the "Jumbo" format mount designed for oversized horizontal stamps. This all-transparent version is the gold standard for collectors who want a "floating" effect for their largest stamps, ensuring the album page's color or design is visible through the mount. It is also the ideal choice for inspecting the reverse of high-value "Jumbo" issues without needing to handle the stamp.
Size C (Jumbo Horizontal): Specifically engineered for oversized stamps that are much wider and taller than standard commemoratives.
Archival Integrity: Made from 100% oriented polystyrene, which is acid-free, plasticizer-free, and chemically inert. It will not shrink or react with the stamp's ink or gum, providing long-term museum-quality protection.
Maximum Transparency: Both the front and back are crystal clear. This is essential for large stamps where verifying watermarks, gum condition, or "back-of-the-book" markings is a priority.
Twin-Weld Security: Features parallel welds at the top and bottom. This "sleeve" style holds the large stamp securely in place while allowing essential air circulation to prevent moisture traps.
Horizontal Split-Back: The clear backing is split horizontally across the middle. Gently flexing the mount opens the split for touch-free insertion with stamp tongs, protecting the corners from bending.
| Feature | Specification |
| Size Designation | Size C (52/36) |
| Dimensions | 52mm Wide x 36mm High |
| Orientation | Horizontal (Landscape) |
| Color | Clear (Transparent Front and Back) |
| Quantity per Pack | 15 Mounts |
| Primary Use | Jumbo Horizontal Commemoratives and Souvenir Sheet Singles |
This large-format mount is the standard solution for several specific philatelic items:
U.S. "Jumbo" Stamps: Fits the modern oversized commemoratives and high-value issues that exceed the standard 40mm width.
U.S. Souvenir Sheet Singles: Perfect for mounting individual stamps removed from large 1930s sheets (like the Byrd Antarctic or National Park issues) or modern commemorative souvenir sheets.
Panoramic International Issues: Ideal for the wide horizontal stamps often issued by Russia, China, and Japan.
Large Canada Commemoratives: Fits several of the wider horizontal Canadian issues from the 1970s to the present.
Because these mounts are quite large (52mm wide), they require a stable anchor to prevent sagging on the page. Use a barely damp cotton swab to apply a thin, continuous line of moisture across the entire top edge of the back. Avoid using too much water, as "bubbling" or watermarks will be visible through the clear plastic.