Concurrent Submit | zhenzhen-video-v31-lowprice

A video node with a fixed length - 8 seconds, no choice - and three model tiers behind one dropdown. zhenzhen-video-v31-lowprice is the pack's V3.1 video workhorse, and its Concurrent Submit wrapper queues it through the 10-slot video pool.

The README's 20260726-1 note explains the shape: the node merged V3.1 Fast and Quality, then added Lite as a third tier that only does fixed 8-second text-to-video. So the three models are:

• zhenzhen-video-v31-fast - the cheap, quick tier.
• zhenzhen-video-v31-quality - the better-looking tier.
• zhenzhen-video-v31-lite - fixed 8s text-to-video only; the most constrained and presumably cheapest.

That Lite tier is the whole reason seconds is locked at 8. The node was built to hold both the older flexible models and the new fixed-length one, and the fixed length won the widget.

How it works

Standard concurrent wrapper: mirror the original's inputs, validate, drop into the bounded video pool (10 workers, COMFLY_VIDEO_CONCURRENCY to tune). Output is a task (COMFLY_VIDEO_FUTURE) → Concurrent Collect Videos (10) → VIDEO tensors in connection order + status.

Inputs that matter

• model - fast / quality / lite. This is the real quality-vs-cost decision. Lite if you only need an 8s draft; quality when the clip has to survive.
• prompt - the scene. Multiline.
• seconds - 8. It's a single option. Don't hunt for a longer clip here; this node is the 8-second house.
• resolution - 720p, 1080p, 4k. The cost dial. Lite plus 4k is an odd combination, but the node will happily do it.
• ratio - 16:9 or 9:16. Vertical and horizontal, that's it.
• image1–image3 - reference images for image-to-video. Lite is text-only per the README, so if you're feeding refs you should be on fast or quality.
• api_config - zhenzhen-seedance2-low-price-api-settings, domestic key from api.seedance.nz.
• seed - cache-control only.

Output: task (COMFLY_VIDEO_FUTURE) → Concurrent Collect Videos (10).

Install

ComfyUI Manager → search "Comfyui-zhenzhen" → install → restart, or:

cd ComfyUI/custom_nodes
git clone https://github.com/T8mars/Comfyui-zhenzhen

No model files, API key required.

Where people get burned

• You can't change the length. This is the top confusion. If you need 15 seconds, this node isn't it - V3.1 here is an 8-second product. The author kept old Fast/Quality workflows compatible, but the length got fixed for everyone.
• Lite is text-only. Feeding reference images to Lite doesn't make it image-to-video; it makes it ignore you or error. Use fast/quality for refs.
• 4k on the fast tier. Manage expectations - "4k" here is a resolution flag on a budget model, and video 4k jobs are where this pack bills the hardest. Draft at 720p.
• Video pool, ten slots. Pair with Concurrent Collect Videos (10), not the image collector. And remember the timeout-≠-failure rule: check the site's async tasks before re-billing a "failed" video.

The 8-second fixed length is genuinely weird until you remember it's a product decision, not a bug: the pack wanted a cheap, predictable, batchable short-video tier. Treat it as exactly that - the bulk short-form tier - and keep the flexible video nodes for when you need length control.