Refractive Index:
1.700 – 1.799


ULC witness samples come with a Refractive Index (Nd) of 1.400 and higher. They are made in America, offering high quality at an affordable price. Characteristics of our witness samples include:

  • Many Popular Glass Types: Select from a large assortment of the most popular glass types.
  • Laser Etched Part Number: No more problems identifying material. The part number is laser etched on the edge and can be cross-referenced to the material type.
  • Inspected per MIL-PRF-13830B: Each sample is inspected for surface quality.
SKU: UL-WS-157 Category:

Additional information

Weight 0.03 lbs

DEDF785258, E-LASF017, J-LASF017, L-LAM60, N-BASF64, N-KZFS8, N-LAF21, N-LAF34, N-LAF35, N-LAK10, N-LAK33A, N-LAK34, N-LAK8, N-SF1, N-SF10, N-SF11, N-SF14, N-SF4, N-SF56, S-BAH28, S-LAH51, S-LAH64, S-LAH66, S-LAL10, S-LAL18, S-LAL59, S-LAL8, S-LAM2, S-LAM52, S-LAM55, S-LAM7, S-NBH51, S-TIH10, S-TIH11, S-TIH14, S-TIH18, S-TIH3, S-TIH4, S-TIH53, S-YGH51, SF-1, SF-10, SF-11, SF-14, SF-4, SF-56A, TAF-1


25.00mm ±0.20mm


3.00mm +0.20mm/-0mm


< 1 wave @632.8nm

Surface Quality



0.50mm ±0.13mm FW x 45°

Clear Aperture

80% min