> For the complete documentation index, see [llms.txt](https://knowledge.illumina.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://knowledge.illumina.com/library-preparation/general/library-preparation-general-reference_material-list/000002335.md).
# Plate layout for TruSeq Combinatorial Dual (CD) indexes
The following table shows the plate layout for TruSeq RNA CD Indexes (catalog number 20019792) and the obsolesced TruSeq DNA CD Indexes (catalog number 20015949; last order date was February 24, 2023). These index kits were formerly named TruSeq HT (high throughput) Indexes.
The Index Adapters Pooling Guide, linked [here](https://support.illumina.com/downloads/index-adapters-pooling-guide-1000000041074.html), contains this table along with recommended index combinations for low-plexity library pooling.
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| *For any feedback or questions regarding this article (Illumina Knowledge Article #2335), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000002335%20-%20Library%20Preparation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |
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