There are many ways to protect the modern notebook computer. The Tech21 Impact Slip Leather Case for MacBook Pro 15” is a worthy additon to your list of options.

And protect your notebook computer you must, as even the most careful of owners can see their valued machine fall prey to annoying scratches and dents as soon as it leaves the security of the home or the office desk.

Tech21 has a range of slip cases – minimalist soft leather covers – that literally just slip over the laptop frame to afford it some essential protection while out and about. 

There are no extra pockets or flaps for accessories, nor carry handle or shoulder strap. But with a notebook in such a slip case, you can be more confident about its safety when then placing it in a regular shoulder bag or rucksack. 

This is no simple leather jacket for the MacBook Pro though. Tech21’s stock in trade is impact protection through the use of crafty synthetic polymers – specifically, a compound that’s called D3O.

D3O is an elastomeric polymer that has liquid, gel-like viscosity under normal room temperature conditions. But when subject to a sudden physical shock, it hardens briefly into a much tougher substance.

We’ve seen this material before in Tech21 iPhone and iPad cases, as well as the original Samsung Galaxy Tab, where leather or moulded rubber cases are lined with the D3O gel, always produced in a lurid orange colour for easy recognition.

This time, Tech21 has lined the leather slip case with flat sheets of the shock-absorbing substance. So both front and rear panes are covered across the width and height of the case. 

Tech21 slip case for MBP front

The Tech21 Impact Slip Leather Case for MacBook Pro 15: it's also available for the 13in Apple MacBook Pro

The Impact Slip Leather Case is a beautifully made cover, using high-grade nappa leather on the outside, with a soft micro-fibre lining inside. Stitching is perfectly precise all around, with a row of orange stitching below the flap as a subtle clue to the brand. 

Tech21 slip case for MBP rear

Rear of the Tech21 Impact Slip Leather Case for MacBook Pro 15in

The D3O must be a very thin sheet placed between those two layers though: the overall thickness of the slip case is still only 2.5mm.

The fold-over flap helps cover the top opening, and this simply tucks into an open seam to keep it closed. We would have preferred a more secure fastening, to ensure the laptop will never slide out if the case should be picked up upside-down. A magnetic clasp, for example, might add more confidence here.

There is no obvious sign of extra D3O running around the circumference, where the laptop needs most protection should it be dropped – the edges and corners are the areas that demand the best cushioning. The protruding leather seam may help here though.

Versions of the Impact Slip Leather Case are made for the 13in and 15in Unibody MacBook Pro. For owners of the 11in and 13in MacBook Air, there's also an alternative jacket leather case which covers the laptop while it's in use.

There’s currently no case customised just for the thinner 15in Retina display model. We did successfully use this case designed for the chunkier Unibody model with the new Retina MacBook, although that model’s slimmer chassis meant it was not quite so snug inside. Tech21 tells us it will be making a case specifically for the MacBook Pro with Retina display.

Used as intended with the 2009-style MacBook Pro, the case is a comfy fit, yet not too tight to hinder it sliding inside. Holes in the bottom, four each corner, prevent an airtight seal from making the laptop ‘stick’ when you load or unload.

We also found this case neatly fitted our older, slightly smaller, Early 2008 15in MacBook Pro.

Tech21 Impact Slip Leather Case for MacBook Pro 15in: Performance

So how well does the D3O slip case protect a laptop inside? The answer is we just don’t know.

We’ve seen some quite dramatic recorded demonstrations of the efficacy of D3O, such as heavy hammer blows to a finger buried in the putty-like raw material. But we were not inclined to try any similar real-life testing of this case, given the precious cargo inside.

Short of dropping our MacBook down a staircase, or even dropping to the floor, all we can say is that the Impact Slip Leather Case feels like it ought to help the laptop shrug off some glancing or non-terminal blows.

It’s a relatively weighty sleeve, too, weighing 400g. This actually lends it an air of real durability, like a motorcyclist’s leather suit.

Tech21 Impact Slip Leather Case for MacBook Pro 15”: Specs

  • Black leather slip case
  • D3O polymer sheet protection front and back
  • micro-fibre inner lining
  • 401 x 288 x 22mm
  • 400g
  • Black leather slip case
  • D3O polymer sheet protection front and back
  • micro-fibre inner lining
  • 401 x 288 x 22mm
  • 400g


The Tech21 Impact Slip Case for MacBook Pro 15in is a superbly finished leather case, using premium materials. We can’t truly vouch how much protection it adds but it should help keep your laptop far safer than with cases using soft materials like neoprene.