* The L521 is our most popular model for carrying 400mm and 600mm lenses. All the L521 models (a, b, c etc.) use the same base, but come with different lids which adjust the overall height of the case.
* Case features PolyCore™ case with semi-rigid sidewalls & bottom — an exclusive Kinesis design offering semi-rigid side walls yielding more protection than traditional soft-side cases.

Please Note: This case is sized to fit full-size DSLRs bodies (with a little extra room so you can reach in and around the body) and 600/4 or 400/2.8 lens. You may find the 300/2.8 lens dwarfed by the large inside diameter of this case. We highly recommend the L029 Foam Insert when using a 300mm or 500mm with this case. Otherwise choose the more compact E970, L311 or L511 instead.
Product Update: We have transitioned from a solid nylon fabric pocket (as shown in most product photos) to a mesh pocket as shown in the detail shot.

- 400/2.8 lens with full-sized DSLR body attached (with quick-release plate attached) and hood reversed.
- Nikon 600/4 VR lens with a large (D3) body attached, hood reversed with the leatherette cap in place.
- Canon 600/4 IS lens w/o body attached but with the hood reversed with the leatherette cap in place.
- We are getting reports that the new Nikon 600/4 lens (2011) and stock leatherette lens hood will not fit inside this case. The diameter of the case is too small. We recommend use of the aftermarket Don Zeck lens cap instead of the Nikon OEM “sock.”.
- 300/2.8, 500/4 or 200-400/4 lenses with a full-sized DSLR body (& quick-release plated attached) with hood reversed, or in some instances, with the hood in the shooting position (measure your extended rig and compare to “height” dimensions below). We highly recommend the L029 Foam Insert when using these smaller diameter lenses. Otherwise choose the more compact L311 or L511 case.

- Nikon 300/2.8 VR in L521, L521a or L521b: Fits with hood attached and in the shooting position + 1.7 teleconverter + D2x body (June 2007)
- Nikon 600/4 VR w/ RRS tripod foot in L521, L521a or L521b with hood reversed, body attached and with leatherette cover on. “The 600 lens fits once I got it started. It is snug, but it fits. To remove it I have to use a strap attached to the lens — it comes out easily though.”(August 2008)
- “The L521a long lens case fit my Nikon [VR] 600mm f4 just fine [w/ Nikon leatherette cap or sock]. It is a snug fit with the lens slip cover in place but it is easy to extract the lens from the case using the attached strap and I prefer it to be a snug fit rather than having the lens slide around inside the case.” (May 2009)
- “My L128 Padded Deep Extension Lid arrived today and is now attached to my L521 Long Lens Case. It holds my Canon 600mm f4 L IS USM lens with the hood extended and a Canon 7D with 1.4 X tele-extender attached.” (August 2010)
- “The Nikon 600/4 VR with Don Zeck lens cap, RRS foot and a D2X body attached fits OK into the L521 with the regular flat lid.” (July 2011)
- Canon 800/5.6 IS in L521, L521a or L521b with hood reversed and body attached. “It fits the 800mm lens very easily with plenty of room on top for a lens and body such as the EOS 1Ds Mark III. There is plenty of space for the lens to fit in and out of the L521” (June 2008)

Lower Position:
- One A257 or M330 can be attached in the lower center of the case (standard position & shown in photos).
- Two single-wide pouches (E110, E280 etc.) can be attached to either side of the lower A257, covering the collapsible pockets. Alternately, a double-wide pouch (A257, M330 etc.) can also be attached to either the left or right of the standard A257 Body Pouch, but this attachment location is a little loose which may cause the pouch to shift around a little, unless secured with a Y205 strap.

Upper Position:
- The upper part of the case will house AN equal amount of pouches, except it has additional attachment points, so two single-wide pouches can be attached in the center. Back (flat) Side of the Case
- A double-wide pouch (A257, M330 etc.) can be attached to the lower back or flat part of the case, although this disables use of any backpack harness or may make using a shoulder strap awkward. Tripod Use Remove the A257 center pouch (shown in photo above) and replace it with a T164 or T317 pouch for attaching a tripod (see this page for pix). Attach a Y204 to the top of the case to hold the top part of the tripod. The A257 can then be reattached to the upper or lower part of the case, slightly off center.

Double-wide allotment on a pack frame.
U.S./Imperial 20-7/8h* x 7-7/8" dia I.D.** 22h x 10-1/4" dia O.D.***
Volume = 1190 cu in
Weight with A257 pouch & shoulder strap: 4 lbs. 8 oz.

Metric 53h* x 20cm dia I.D.** 56.5h x 25.8cm dia O.D.***
Volume = 19.5 lit
Weight with A257 pouch & shoulder strap: 2kg

*Inside Height: There is a little give in the soft foam lid & the Velcro, allowing a lens/body combo up to 54.5cm (21-1/2") to fit inside this case. **Inside Diameter: The “dia” dimension is the maxium diameter of the front element and/or lens cover that will fit inside this case. The circumference of this case is 71cm (27-7/8") and measures the entire inside perimeter of the "D" shape of the case. It is larger than 3.14 times the diameter to allow extra room for the lens tripod foot. To reduce the diameter of the bottom of the case consider L029 foam insert. **Outside Diameter: Please note than the outside diameter of the lid is 28cm (11").