Happy Holidays to All!
Case w/o external pouches.
Rear/side view with lid partially pulled back.
Mesh pocket with an elastic closure fits most bottles up to 1 liter in size.
L321 — PolyCore™ Long Lens Case 300 (w/ shoulder strap)
Metal slider on the back of the case for attaching a backpack harness (covered by the lid when not in use).
Under the lid is a removable piece of Velcro for faster field use.
Top handle.
D-shaped profile of case. Zippered pocket under lid.
Attach a T164 to the bottom (or left side) and add a Y204 strap to carry a tripod. Use a ballhead pouch to carry the tripod upside down instead of a T164.
L511, NOT L321 shown. Attach a backpack harness to any long lens case.
L511, NOT L321 shown. A monopod will fit in the side pocket and is secured to the top using built-in straps.
Rear view of lid.
We’ve changed our logo! Old label on the left—new one on the right. Some current inventory may have old label.
Inside dimensions for L321, L522 & L622 PolyCore cases. 195mm = 7-¾", 203mm = 8", 190mm = 7-½".
This photo illustrates just how rigid and tough a PolyCore long lens case is.
A257 body pouch attached with Y515 Shoulder Strap.
A257 body pouch attached with Y515 Shoulder Strap.
A257 body pouch attached with Y515 Shoulder Strap.

L321 — PolyCore™ Long Lens Case 300 (w/ shoulder strap)

A robust shoulder-style case for 300/2.8 lens with a body attached and with the hood reversed. Also fits a 400/2.8 & many 500/4 lens without a body attached and with the hood reversed.
41cm (16") I.D. Height

  • This case was originally designed to carry a 300/2.8 lens with a body attached, but with the subsequent introduction of the L311 you may find that case more suitable because of it’s more compact design. This case, however, will offer more protection than the L311.
  • This case uses the Kinesis exclusive PolyCore™ construction with semi-rigid sidewalls & bottom.
  • Converts to a backpack with the addition of the H255 harness.
  • Please note that this case has a slip-on lid that fits with a partial Velcro and buckle method. If you want a full zippered lid, then choose the smaller diameter L311 or L511 (but these cases are too small for most 400/2.8 or 600/4 lens hoods).

L029 Accessory Note:  This case is sized to fit a full-sized DSLR or mirrorless bodiy (with a little extra room so you can reach in and around the body) and 300/2.8 lens. You may find the 300mm lens dwarfed by the large inside diameter of this case. We recommend the L029 Foam Insert when using a 300mm or 500mm with this case. Otherwise choose the more compact E976, L311 or L511 instead.  

Mesh Pocket Note: We have transitioned from using a solid nylon fabric pocket (as shown in most product photos) to a mesh pocket as shown in the detail photo.

Fits the Following

  • 400/2.8s lenses without body attached. It may fit some 600/4 lenses without a body attached and with hood reversed (with leatherette lens cover).
  • 300/2.8 w/ teleconverter, 400/4, 200/2.0 lens & a DSLR body (with quick-release plate attached) and hood attached in the stowed postion (with leatherette lens cover). For a smaller case for your 300/2.8 lens only, without a body attached, select the E660 lens pouch instead.
  • Some 500/4s without a body attached — check and see if your lens, measured from the end of the cap to the rear body cap, is no more than 42.5cm (16-3/4").

External Attachment Options

Lower Position
-One A257 or M330 can be attached in the lower center of the case. Another similar double-wide pouch can be attached above it, centered on the upper part of the case (although the bottom pouch may be difficult to access).

-A double-wide pouch (A257, M330 etc.) can be attached to either side of the lower side of the case, but this attachment location is a little loose which may cause the pouch to shift around a little, unless secured with a Y205 strap.

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 belt or pack frame. (Realistically, this case is too large to conveniently worn on a belt). 

The sidewalls are constructed with our exclusive 13mm-thick semi-rigid PolyCore™ and the lid uses 10mm closed-cell foam. The bottom also uses a piece of stiff 13mm PolyCore™, plus an additional layer of 6mm closed-cell foam.

Long Lens Case Instruction Sheet (PDF)

16h x 7-7/8" dia I.D.
17-1/2h x 10-1/4" dia O.D.
Volume = 896 cu in
Weight with A257 pouch & shoulder strap: 4 lbs.
Weight w/o A257 pouch and shoulder strap: 3 lbs 7.5 oz 

41h x 20cm dia I.D.
44.5h x 25.8cm dia O.D.
Volume = 14.7 lit Weight with A257 pouch & shoulder strap: 1.8kg
Weight w/o A257 pouch and shoulder strap: 1.56kg

Height (I.D. or Inside Dimension): There is a little give in the soft foam lid (15mm or 5/8"), allowing a lens/body combo up to 42.5cm (16-3/4") to fit inside this case.

Diameter (I.D. or Inside Dimension): this is the maximum 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.
Diameter (O.D. or Outside Dimension): Please note than the outside diameter of the lid is 28cm (11").

Designed & Crafted in USA

made in usa