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Earth River SUP 8-9 RIVER S3R-MKII - PURPLE Inflatable Paddle Board (8'9"x35"x6")

Earth River SUP 8-9 RIVER S3R-MKII - PURPLE Inflatable Paddle Board (8'9"x35"x6")
Regular price $ 899.00
Sale price $ 899.00 Regular price $ 899.00
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ADD an elite performance level SUP paddle and gear with your board – select the checkbox for your add on/s – then use the ADD TO CART button to add all items selected to the cart.

ADD a PADDLE with an ERS board purchase
ADD a PADDLE with an ERS board purchase
$ 99.00 $ 199.00
ADD an ERS 12VDC Pump (OPTIONAL ERS GO Battery) with an ERS Board Purchase
ADD an ERS 12VDC Pump (OPTIONAL ERS GO Battery) with an ERS Board Purchase
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ADD a LIFEJACKET or PFD with an ERS board purchase
ADD a LIFEJACKET or PFD with an ERS board purchase
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ADD a GEAR PACK with an ERS board purchase
FREE$ 79.00
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ADD a SUP LEASH with an ERS board purchase
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The Earth River SUP 8-9 RIVER S3R-MKII is the compact size of ERS's dedicated whitewater board — 8'9" long, 35" wide, 6" thick, and just 19 lb. Like its 9'7" sibling, it's designed to excel at all areas of river paddling: attaining upstream to play spots, river surfing, running rapids, creeking, and expeditions.

Who Is The 8-9 RIVER For?

The 8-9 RIVER is for river paddlers who want the S3R-MKII's whitewater shape in its shortest, lightest form. The compact length is naturally suited to quick direction changes on a wave and in tight water, and at 19 lb it's easy to carry down a bank, portage around a drop, or hike to a remote put-in.

Like the 9-7, it's the same purpose-built river board underneath — the same ULTRA RIVER construction, the same short-fin setup, the same 48-month warranty.

8'9" | 35" wide | 6" thick | 19 lb board weight | Riders up to 250 lb

Why Riders Choose The 8'9" RIVER MKII

Everything the 9-7 does, in a smaller board. Attain upstream to play spots, surf it, run it, creek it, paddle expeditions on it — in a board that's 10" shorter and 2 lb lighter than the 9-7. The 35" width and 6" thickness keep it stable and floating high over river features.

Quick in tight water. The short waterline spins faster on a wave and fits lines a longer board has to work around — creeks, boulder gardens, and small play spots. The X-Ultra Grip deck pad and the contoured tail pad hold your stance through the rear-foot moves those places ask for: bottom turns, tail drops, and submerged tail pivot turns.

River construction, river warranty. The ULTRA RIVER core construction with X11 reinforcement layers in key areas is ERS's build for the water that punishes boards hardest — and it's backed by a 48-month warranty.

Built For Years Of Real Use

Rocks, shallow landings, and repeated impacts are just part of river paddling, and the MKII is built for them: ULTRA RIVER core with X11 reinforcement in the areas that take the most wear, at a board weight of just 19 lb. High-grade stainless steel D-rings at the nose, tail, and forward deck take a quick-release leash, tow line, or expedition tie-downs.

The Fin System

The LAKE RIVER COAST™ (LRC) Fin System on the RIVER MKII is a river-specific setup: two short US center fins (4.5" and 3") and two sets of two side click fins (4.5" and 1"), all packed in a padded ERS fin and accessories bag. The short fins suit shallow moving water, and the tuned toe-in angle preserves control; the center fin box accepts any US Fin Box-compatible fin plus FCS Connect™ tool-less center fins if you want to run something else for deeper water.

Full Specs

Length 8'9"
Width 35"
Thickness 6"
Board weight 19 lb
Rider weight range Up to 250 lb
Construction ERS ULTRA RIVER Core Construction (X11 reinforcement)
Fin system LAKE RIVER COAST™ (LRC) — two US center fins (4.5", 3") + two sets of two side click fins (4.5", 1"); US Fin Box + FCS Connect™ compatible
Deck pad X-Ultra Grip texture with contoured tail pad
Included Deluxe rolling backpack, high-pressure double-action pump, padded fin/accessories bag, 48-month warranty
Recommended use Whitewater: river surfing, running rapids, attaining upstream, creeking, river expeditions

Safety note for whitewater use

A standard ankle leash is not recommended for whitewater paddling. Use a quick-release leash, wear a helmet, and wear an inherently buoyant life jacket — all are important safety equipment in moving river water.

Inflation

The ERS 12VDC 20PSI Electrical Pump inflates this board to 15PSI in approximately 11 minutes. The included double-action manual pump inflates on both the downstroke and upstroke, cutting inflation time and effort roughly in half.

Choosing Between The 8-9 And The 9-7

Both sizes share the same construction, fin setup, deck pad, and warranty — the choice is about length and capacity. The 8-9 supports riders up to 250 lb and is quicker to spin on a wave, easier in tight creeks, and easier to carry. The 9-7 supports riders up to 290 lb and carries more length for momentum on attainment moves, bigger water, and loaded expedition paddling. Lighter paddlers and wave-focused riders tend toward the 8-9; heavier paddlers and those who run bigger stretches or carry gear tend toward the 9-7. Call the number below and we'll help you match the size to your river.

What's Included

Every 8'9" RIVER MKII ships with a deluxe rolling backpack, a high-pressure double-action pump, the padded fin and accessories bag with all included fins, and a 48-month warranty.

Contact a paddling expert on 877-777-1769 for our best package deal price and our review of the pros and cons of the Earth River SUP RIVER Series.


Related Reading:
- How to Choose a SUP Board for Whitewater and River Surfing
- When Should You Consider Buying A 6-Inch Thick Inflatable SUP?
- Why Buy From Pumped Up SUP?
- Which Earth River SUP Board Should I Buy?

FAQ

What kind of paddling is the 8-9 RIVER S3R-MKII built for?
All areas of river paddling, not just downriver: attaining upstream to play spots, river surfing, running rapids, creeking, and river expeditions. It's the compact size of ERS's purpose-built whitewater board.
What size paddler can ride the 8-9 RIVER?
It supports riders up to 250 lb. The 35" x 6" footprint carries that range while staying stable in current — a compact board that still fits most paddlers.
Should I choose the 8-9 or the 9-7 RIVER?
Both share the same construction, fin setup, deck pad, and 48-month warranty — the choice is length and capacity. The 8-9 (19 lb, riders up to 250 lb) is quicker to spin on a wave, easier in tight creeks, and easier to carry; the 9-7 (21 lb, riders up to 290 lb) carries more length for momentum on attainment moves, bigger water, and loaded expeditions. Lighter and wave-focused paddlers tend toward the 8-9.
Why is it so wide and thick for its length?
The 35" width gives the 8-9 the stability moving water demands, and the 6" thickness adds the volume to ride over river features. On a board this short, that width and thickness are what keep it steady in current.
What construction does the 8-9 RIVER use?
ERS ULTRA RIVER core construction with X11 reinforcement layers in the areas that take the most wear — built to shrug off rocks, shallow landings, and repeated impacts — at a board weight of just 19 lb. It's backed by a 48-month warranty.
What fin setup does it come with?
The 8-9 RIVER runs a river-specific LAKE RIVER COAST™ setup: two short US center fins (4.5" and 3") and two sets of two side click fins (4.5" and 1"), packed in a padded ERS fin and accessories bag. The center fin box also accepts any US Fin Box-compatible fin and FCS Connect™ tool-less center fins for deeper water.
Is it good for river surfing?
Yes — river surfing is one of the 8-9's core uses, and the compact 8'9" length is naturally suited to quick direction changes on a wave. The X-Ultra Grip deck pad and contoured tail pad hold your stance through surf maneuvers.
Do I need special safety gear for river paddling?
Yes — a quick-release leash rather than a standard ankle leash, plus a helmet and an inherently buoyant life jacket. All three matter any time you're on moving water.
What's included with the 8-9 RIVER S3R-MKII?
A deluxe rolling backpack, a high-pressure double-action pump that inflates on both the downstroke and upstroke, the padded ERS fin and accessories bag with both center fins and both sets of side fins, and a 48-month warranty.