Product description is for Windrider 3400, all models are available and specs are given below.
 
Achieve your optimal hiking speed, efficiency and comfort with the 3400 Windrider ultralight backpack. Made with durable, 100% waterproof Dyneema® Composite Fabrics (formerly Cuben Fiber), this pack is ideal for long-distance trails that require more time between resupplies. Weatherproof your kit with our Stuff Sacks.
 
FEATURES
Made in Maine USA
Three external mesh pockets -- Makes it easy to see what's in your pockets and allows gear to dry faster
Removable, contoured aluminum stays
Dyneema® Hardline shoulder straps with 3/8” closed cell foam and spacer mesh
1/4” foam back panel pad
Compression System
Roll-Top closure system with side compression straps for vertical compression
Side compression straps for horizontal compression
Top Y-strap compression -- Designed to secure gear
Dyneema® Hardline dual-density hip belt with 1/8” closed cell rigid foam, 1/4" closed cell foam and spacer mesh
Dyneema® Hardline zippered pockets on hip belt with #5 YKK zipper
Adjustable sternum strap with self-tensioning elastic
Ice Axe loop
Hydro port and internal mesh hydro sleeve
Four exterior triglide buckles for optional pack accessory straps
Proprietary seam sealing on all side seams and behind all sewn-on pack features
 
Load capacity: Up to 40 lbs
Materials:
Body: 50D Dyneema®/Poly hybrid for white version
Body: 150D Dyneema®/Poly hybrid for black version
Bottom: Double reinforced 150D Dyneema®/Poly hybrid
External Pockets: Dyneema® Hardline
Volume:
Interior: 3400 cu. in. (55L)
External: 600 cu. in. (9.8L) if applicable
Center pocket: 300 cu. in.
Side pockets: 150 cu. in.
Dimensions:
Top Circumference: 40” (101.6cm)
Bottom Circumference: 33.5” (85.1cm)
Height (fully unrolled): 34” (86.4cm)
Back Width: 10.5” (26.7cm)
 
3400 WindriderWEIGHT
White:Small 1.89 lbs | 30.30 oz | 859g
Medium 1.94 lbs | 31.08 oz | 881g
Large 2.01 lbs | 32.13 oz | 911g
Tall 2.05 lbs | 32.77 oz | 929g
Black:Small 2.09 lbs | 33.40 oz | 947g
Medium 2.13 lbs | 34.04 oz | 965g
Large 2.20 lbs | 35.20 oz | 998g
Tall 2.23 lbs | 35.66 oz | 1011g
 
3400 Porter WEIGHT
Small      1.97 lbs | 31.53 oz | 894g 
Medium  2.02 lbs | 32.38 oz | 918g
Large      2.10 lbs | 33.58 oz | 952g 
Tall          2.13 lbs | 34.00 oz | 964g
 
3400 Southwest WEIGHT
White:
Small      1.92 lbs | 30.69 oz | 870g 
Medium  1.94 lbs | 31.08 oz | 881g
Large      2.04 lbs | 32.59 oz | 924g 
Tall          2.07 lbs | 33.09 oz | 938g
Black:
Small      2.09 lbs | 33.40 oz | 947g 
Medium  2.13 lbs | 34.04 oz | 965g
Large      2.22 lbs | 35.52 oz | 1007g 
Tall          2.24 lbs | 35.91 oz | 1018g