D began marketing polyurethane foam insulation products under the brand name 'Coro-foam.' D sold 'Coro-foam 340' insulation to Thomas Kreis, who was in the business of selling and installing insulation. Kreis contracted with P to apply the Coro-foam insulation with a spray applicator to the inside walls and ceiling of the vehicle repair shop owned by P. Kreis gave P a brochure from Cook describing the properties of Coro-foam insulation. Kreis conducted a demonstration to show the flame-retardant characteristics of the insulation. A fire destroyed P's building when sparks or a hot metal slag from a welder used in their vehicle repair shop ignited the Coro-foam insulation. The building was destroyed in a matter of minutes. P sued D. P testified at trial that the brochure P got described Coro-foam as flame-retardant. D objected. P got the verdict. D appealed in that P’s testimony was not the best evidence because P had identified a brochure similar to the one destroyed in the fire it was incumbent upon P to introduce that brochure as a duplicate.