Free Shipping on all orders over $99.00 
(Excludes International, Alaska and Hawaii)
Holiday Season Shipping
All shipping carriers are experiencing delays and irregular service 
We will do our best to notify you and ship your order as quickly as possible
Let's all be patient and allow our shipping partners to do their best
Please contact us if you have specific shipping concerns

MagnaPen - Whelping Box Extension Pen

Whelping Box Extension Pen
Whelping Box Extension Pen
Whelping Box Extension Pen
Whelping Box Extension Pen
Whelping Box Extension Pen
$250.00 - $770.00


Eligible for FREE Shipping (Eligible for FREE Shipping)
  • Description
  • Specifications
  • Product Reviews

Our Whelping box extension, The MagnaPen Extension pen, is the perfect addition to the MagnaBox Next Generation Professional Whelping Box.  The whelping box extension pen easily attaches to the front of the whelping box and uses the same hook and slot joints as the whelping box.  The MagnaPen incorporates the same 1/3 and 2/3 height doors for easy access and control. It is simple to clean and keep clean.  FDA approved, HDPE plastic (a common material for kitchen cutting boards) is UV resistant and will not rust, stain or discolor.  Unlike wood and other plastic whelping boxes, the MagnaPen Extension Pen has no cracks, crevices, porous or painted surfaces to retain contamination.

The MagnaPen is available in either solid sides (like the MagnaBox) for controlling drafts and easy clean ability or slatted sides to allow for airflow and visual interaction.

Quality solid materials along with unique hook and slot connectors and a lightly textured surface make cleanup a breeze.  Easily wipes clean with a rag and sanitizing solution and when disassembled can be quickly cleaned and sanitized with a power washer.  There are no plastic welds, caulk joints, hidden slots, fasteners, or corrugations that capture and retain contamination and are nearly impossible to clean and sanitize.

Assembly requires no tools and no fasteners.  No small parts to insert while aligning bulky components.  No Velcro to wear out or replace.  No adhesive or painting required.

Simply align, insert, and slide into position the unique hook and slot joints in the corners.  Remove the puppy rails from the MagnaBox and then attach the MagnaPen to the existing slots on the front of the MagnaBox.

Available in the following five standard sizes to match the MagnaBox as well as custom sizes on request.  Choice of either solid or slatted sides.

XX-Small - 24" x 24" x 12" tall (inside dimensions 19 1/4" x 21 1/4")

X-Small – 30" x 30" x 15" tall (inside dimensions 24 3/4" x27 1/4")

Small – 36" x 36" x 18" tall  (inside dimensions 30 1/4" x 32 3/4")

Medium - 42" x 42" x 18" tall (inside dimensions 36 3/4" x 39 1/4")

Large – 48" x 48" x 20" tall (inside dimensions 42 3/4" x 45 1/4")

X-Large – 54" x 54" x 24" tall (inside dimensions 48 3/4" x 51 1/4")

All outside dimensions are nominal.  Extension pen fits inside the dimensions noted below.






Extra Small

30 inches

30 inches

15 inches

22 lbs


36 inches

36 inches

18 inches

30 lbs


42 inches

42 inches

18 inches

40 lbs


48 inches

48 inches

20 inches

52 lbs

Extra Large

54 inches

54 inches

24 inches

65 lbs


There are no customer reviews for this product. However, you can be the first person to add a review for this product.

Add Review

Add Review


(Your browser will be redirected back to this page)



Welcome guest,


Shop by Price

Subtotal: $0.00

Join our Newsletter