Open-end wrenches have been used for decades and their design is timeless. Humans have had a long time to perfect them, as there is evidence of their existence dating as far back as the 15th century. They come in all sizes in both metric and SAE, ranging from just a couple millimeters all the way up to a few inches. They come in thin and thick profile, and can be used for all types of automotive repair jobs. They are arguably one of the most ubiquitous automotive tools, being found in almost every auto shop, home garage, or mechanics tool set in the world today.
As wrenches have evolved, so have cars. With the increasing focus on fuel economy as well as adding more and more creature comforts to make driving more pleasurable, space to work has become tighter and tighter. The most modern cars have to really squeeze components in to make cars with modern features viable. Unsurprisingly, this makes space for wrenching tight, and it is more common to find bolts with limited access that can’t be reached by normal open wrenches since they are too thick.
Fortunately, tool makers caught onto this trend long ago and started making special open wrenches with a thinner profile to give a mechanic the ability to access bolts in tight spaces. So that you don’t find yourself in a “tight spot” (get it?), we recommend that mechanics have a thin wrench set in their tool kit as the cost of entry is low and the convenience factor is extremely high when you encounter a tough to access bolt deep within your engine bay.
The Best Thin Wrench Set
Since thin wrenches have a more limited market, it is sometimes hard to find a cost effective set. However, we tend to like the sets made by Grip as they offer a nice balance between cost and quality.
Grip 9 offers both metric and SAE wrenches. These wrenches are double sided, meaning that they have a wrench head on each end of the tool. The 9-piece metric set has a wrench size range that includes 18 different sizes: 8mm x 9mm, 10mm x 11mm, 12mm x 13mm, 14mm x 15mm, 16mm x 17mm, 18mm x 19mm, 20mm x 21mm, 24mm x 27mm, and 30mm x 32mm. Similarly, the SAE 7 piece set has a size range that includes 14 sizes: 3/8in x 7/16in, 1/2in x 9/16in, 5/8in x 11/16in, 3/4in x 13/16in, 7/8in x 15/16in, 1in x 1 1/16in, and 1 1/8in x 1 1/4in. These size ranges cover the vast majority of bolt sizes that you are likely to encounter when working on your car, especially for any bolt that would require an open wrench to install or remove.
Each wrench has a thin but strong design and the heads have a slightly enlarged tooth profile to provide extra strength during use. Each wrench measures 3mm thick (roughly 1/8″). The wrench set is made via a steel drop forging process which includes shaping material between large forming dies before applying a heat treating process to harden the material, which adds additional strength.
The wrenches are chrome plated for corrosion prevention which ensures durability and also makes them easier to clean as it eliminates the porosity found in raw steel. The complete set comes in a roll-up storage pouch with individual slots for each wrench to make them easy to find when the pouch is unrolled. The rolled pouch is approximately 12 inches in length and less than 3 inches in diameter, so it will easily fit inside your storage cabinets or a deep tool box drawer in your rolling tool chest. At 2 pounds, the complete set is small and lightweight enough to make them portable for mobile mechanic work or even for a roadside repair if you keep a few common sizes in your emergency kit.
As far as available purchasing options, Amazon tends to be the easiest place to find them since they don’t often show up in brick and mortar stores. Overall, a set of open-end wrenches is one the most flexible tools that you can have in your toolbox and Grip makes some of the best thin wrenches available. We give them a high recommendation and think that they will treat you well over the years. Happy wrenching!