Average Daily Light on an Annual Basis (ADLAB) is calculated by measuring a product’s light output at every daylight hour on the 21st of March, June, September, and December. These values are totaled and averaged.
For a fair comparison, the tested systems must have the same L over D ratio, which is the length of the daylighting tube divided by the diameter of the tube opening. Testing must be performed by an independent, certified testing agency.
Valid only for Solatube 160 DS and 290 DS models when used with the Natural Effect Lens
Applies to residential purchases for personal use only
Product must be assembled and installed according to Solatube’s official specifications
Does not apply to newly introduced products from Solatube International, Inc.
Guarantee is valid only for qualifying purchases made on or before December 31, 2017
This guarantee gives you specific legal rights, and you may also have other rights which vary from state to state.
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