The Snyder Industries 275 Gallon Double Wall Tank (SKU 5740102N42) is a self-contained secondary-containment vessel molded from crosslinked linear polyethylene (XLPE) to ASTM D1998. It stands 63 inches tall on a compact 47 x 47-inch footprint, so the containment shell and inner tank occupy the same floor space a single-wall vertical would. The natural white outer wall captures a leak from the primary tank without a separate poly basin. If you are weighing this XLPE double wall tank against a single-wall-plus-dike arrangement, the built-in interstitial space is what earns its place in tight equipment rooms and on curbed pads.
Will it work for your job?
The inner tank holds 275 gallons and carries a 1.9 specific gravity rating, which is at the top of the poly range and gives you real structural headroom for water and heavier potable or utility service. Water fills to roughly 2,294 pounds; at the full 1.9 SG rating the primary is engineered to carry up to about 4,358 pounds of contents. Fittings per the technical drawing include an 18-inch PE threaded/vented top opening and a manway with 15-inch access. The 18-inch fitting is threaded, so it takes a threaded or bulkhead adapter with a gasket sized to your plumbing, and the 15-inch manway is your inspection and cleanout point. Review the technical drawing on this page to confirm fitting positions and heights against your plumbing before you set the tank. The crosslinked (XLPE) construction is built for long-term service when a vessel sits full for years.
Sizing it correctly
Do not fill to the brim. Every ASTM D1998 tank needs freeboard for thermal expansion, and product density changes the usable volume you can actually count on. Our Tank Sizing Calculator and Tank Sizing Guide walk through it, and the guide on Snyder Captor double-wall freeboard sizing per ASTM D1998 shows exactly how thermal expansion and density eat into the 275-gallon nameplate. If this is a fire-water or reservoir role, the fire-water reservoir design guide covers NFPA 22 sizing discipline.
The mistake to avoid
The common error on double wall tanks is treating the 1.9 SG rating as headroom to ignore. That rating governs how heavy a liquid the tank is engineered for, not how much you can stack on an undersized pad. This is a relatively tall, narrow vessel: confirm the pad is dead level and rated for the roughly 4,358-pound load concentrated on the 47 x 47-inch base, and keep the vented 18-inch fitting clear so the interstitial and primary breathe correctly. Wall-thickness fatigue tends to start in the vapor-saturated headspace above the liquid line, not below it; the guide on HDPE wall thickness at the vapor-saturated headspace explains why liquid-side inspection misses it.
This tank ships LTL from the Snyder plant in Marked Tree, Arkansas, with freight quoted live to your ZIP. Use the Freight Cost Estimator for a rate, or call 866-418-1777 to lock in delivery. Have your ZIP and offload details ready and we will get this 275-gallon XLPE double wall tank on a truck to you.
