1. Match the exact product and variant
Length, width, shape, weight, packed size, and sometimes lifecycle vary within a model family. A measurement for one size is not silently assigned to another. OutdoorSpecs names the canonical reference variant and exposes split lifecycle where recorded.
2. Read thermal evidence with its attribution
Reported R-value and ASTM-qualified R-value are not interchangeable labels. Use the evidence state to see whether the number can support a cross-brand ASTM comparison.
3. Compare weight and dimensions on the same basis
Canonical weight must resolve to the reference variant. Dimensions and packed size should be read with the same scope. A model-wide fact may pair with a canonical variant only where the established compatibility rule permits it.
4. Keep price and lifecycle time-bound
Reference price is an observed manufacturer fact with a freshness window, not a guaranteed checkout amount. Historical models remain available as records but are excluded from the default current-market universe.
5. Treat gaps as information
A missing, conflicting, ambiguous, or estimated value narrows what can be concluded. OutdoorSpecs omits a comparison rather than filling the gap or assigning a score.