Yes, the Canon EOS R5 Mark II works with the Delkin Devices POWER CFexpress Type B 128GB — with conditions (see below).
Canon EOS R5 Mark II's Slot 1 accepts CFexpress Type B cards directly; Delkin Devices POWER CFexpress Type B 128GB fits and works for standard Long-GOP recording. This card has no published VPG rating in the DB — Canon's manual states movies require 'a CFexpress card that supports VPG400 or a card with ample performance' for the camera's top-tier 8K RAW mode (400MB/sec. sustained). Confirm this specific card's VPG400 rating before relying on it for RAW/Intra recording.
Conditions for compatibility
Fits Slot 1 (CFexpress Type B). Delkin Devices POWER CFexpress Type B 128GB's VPG rating is not confirmed in the DB — verify VPG400 or higher before using for 8K RAW or Intra-codec recording (400MB/sec. sustained write floor).
“When recording movies, use a CFexpress card that supports VPG400 or a card with ample performance (fast enough writing and reading speeds) for the movie recording quality”
Last verified:
Compatibility inferred from spec rule (citations above are manufacturer-verified)