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REP x PEPIN FAST Series Adjustable Dumbbells: What to Know
The REP x PEPIN FAST Series is a collaboration between REP Fitness and PEPIN, a Canadian adjustable-dumbbell maker, and it's built differently from most selectorized designs on this list: instead of plates stacking on a handle or nesting in a block, metal arms extend and grab the plates you've dialed in. REP sells it in four pair sizes, 65, 85, 105, and 125 lb per pair, so the top end here is roughly double what REP's own QuickDraw or the Bowflex Results Series 552 can reach.
The primary adjustment moves in 10 lb increments via a magnetic pop-pin system: press the pins out, slide to the target weight, and press back in to lock. REP also includes 2.5 lb micro-adjustment plates so you can fine-tune in 2.5 or 5 lb steps on top of the main jumps. The whole assembly is metal, including UHMW liners between plates specifically to prevent steel-on-steel contact and rattling, with a nickel-plated handle and the same volcano-style knurling REP uses on QuickDraw.
On Amazon, this exact product currently shows up under the generic listing title "Adjustable Dumbbell by REP Fitness" (ASIN B0H2NPBRPT) rather than the branded PEPIN name, the specs and images on that listing match the FAST Series description on REP's own site, but shoppers should double-check the weight configuration and product photos before ordering, since the title alone doesn't make the branding obvious. A separate Amazon listing exists for a "REP x PEPIN" bundle (ASIN B0H3J19C6Y) that appears to package the dumbbells with an add-on; we're pointing to the primary standalone listing.
Pricing on REP's own site runs from $899.99 up to roughly $1,500 for the largest 125 lb pair, meaningfully more than every other product in this guide, reflecting both the all-metal build and the sheer weight capacity. Amazon's page could not be loaded live during this research due to bot-verification screens, so confirm current price and configuration before buying.
Key Listed Features
All-metal construction with UHMW liners to prevent steel-on-steel contact
Magnetic pop-pin arm system for primary 10 lb weight jumps
2.5 lb micro-plates included for finer 2.5-5 lb adjustments
Nickel-plated handle with volcano-style knurling
