UNET Selector

Loaders in ComfyUI grab weights the moment they execute, which is fine until you realize the dropdown on a loader is also doing double duty: it's your file picker, your metadata source, and your VRAM gate all at once. UNET Selector breaks that habit. It's a dropdown that only picks. No loading happens when it runs - it returns a unet_info value describing the file you chose, and a separate loader node does the actual work later.

The two inputs are unet_name (the dropdown, populated from the models available in your UNET folders) and weight_dtype. The dtype dropdown is worth actually reading: default, plus fp8_e4m3fn, fp8_e4m3fn_fast, and fp8_e5m2. If you've got a 24GB card or better, "default" is usually fine and you can ignore this. If you're squeezing a big UNET onto less VRAM, fp8 is the lever - fp8_e4m3fn is the standard quality-conscious pick, fp8_e4m3fn_fast trades a bit of quality for speed on hardware that supports it, and fp8_e5m2 is the rougher but lighter option. The one output, unet_info, carries both the file choice and that dtype choice.

Why split the pick from the load? Three genuinely useful reasons:

1. Your workflow survives model swaps. Change the file in one selector, and every downstream node that consumes its info follows along. No re-wiring.
2. Metadata flows with the choice. The unet_info value is the same MODEL_INFO type the pack's metadata nodes consume, so the exact UNET that generated an image gets recorded in the saved file's metadata - the pack's whole reason to exist.
3. Cleaner graphs. One dropdown feeding Load UNET, the metadata pipeline, and a "UNET CLIP VAE To Model Info" bundler beats three loaders doing overlapping jobs.

The flow it's built for: UNET Selector → Load UNET (the "Load UNET" node under Sage Utils/loader) → KSampler, or bundle it with CLIP and VAE selectors through UNET CLIP VAE To Model Info to assemble a virtual checkpoint. It's the same pattern as the pack's VAE Selector and CLIP selectors - learn one, you've learned the family.

One thing to know before you wire it up: a selector alone does nothing. If you replace a loader with this node and press run, you'll get a MODEL_INFO output and no model, and your sampler will complain. It's always half of a pair with the loader. People forget that about this family more than any other gotcha.

Install is the pack standard - ComfyUI Manager (search "Sage Utils") or:

cd ComfyUI/custom_nodes
git clone https://github.com/arcum42/ComfyUI_SageUtils.git

then restart. No models download with the pack; the dropdown lists what you've already placed in your UNET folders.