Im restoring a classic car - the interchangeable crimp molds are great! While I cringed at the cost initially, good tools are not cheap... and this is inexpensive (NOT CHEAP) for what it delivers. Very well made, quality tool for most all the needs in crimping various automotive connectors.Great set of crimper and dies for the price, The case is convenient and stores the crimper and dies securely. Comes with a wide variety of dies. It even has a die that will do large AWG insulated cord end terminals. I believe it can go as large as 6 AWG. Very hard to find one that does large AWG. As for the ratcheting mechanism and the crimp, it does not come close to knipex crimpers. I use the knipex master crimper with die sets almost ever day and there is a huge difference. The crimp action on the Knipex is almost effortless. I even have a dedicated ratcheting insulated terminal crimper from knipex and it is day and night compared to astro pneumatic. That damn thing only crimps insulated terminals and it's $130. The problem is, Knipex will not only break the bank, but it will close your account hahaha. I paid almost $200 just for the master crimper pliers WITHOUT ANY DIES AT ALL!!! THE DIES ALONE RUN FROM $100-$200. Laugh all you want but while you are laughing, I just rewired and repaired a backup generator that provides back up power to hospitals when a natural disaster hits. I bought this astro pneumatic set as a gift for an employee/apprentice of mine. He always complains that he has to use the old style crimpers with no ratchet where you actually have to squeeze to crimp. He has some girly hands for a field engineer. I tried his set out and I was so glad I didn't go cheap on my own tools. This AP set is great for the auto mechanic or electrician but not for us engineers that hold life and death in our hands. Sound pretty over dramatic huh? I would give it a 3.5 but I will round it up to 4 stars. Amazon, please try and get the Knipex tool prices to go down a bit. ThanksGreat valueThis is my first set of ratcheting crimpers. Right out of the gate looking the dies, especially starting with the insolated closed barrel connector, you can tell each side of the die for one individual crimp has a different extrusion height.As others said there is one side designed to crimp the insulation and then there is another side to crimp the barrel holding the wire itself. The colored dot side crimped the insulation, the other side crimps the barrel with the wire.The problem I have with this design is when you are using heat shrink insulated closed barrel connectors.The heat shrink is larger than typical insulated connectors so it does interfere with getting a consistent crimp.There were some heat shrink connectors I couldn't use on them like a spade connector. The heat shrink on both sides of connector were too large for the dies to be able to accept it.Other than that they function as intended and do speed up the crimping process. Getting consistent quality crimps comes with experience. It's a solid tool with good value.But I would think it's pretty important for the manufacturer to tell you that the dies jaws are side specific to the connector.....I just bought this tool and used it on a handful of insulated terminals. Simple and very basic stuff, but the tool works great. Ratcheting handle is terrific because you can squeeze part of the way then relax to re-grip the tool and pressure is maintained so nothing slips. And after getting in a full stroke, the device releases. Every time.I agree with Kandoro that the instructions could be better. When using the A Jaw (and maybe the others, I don't know on that yet), you have to put the terminal in correctly because one side leaves room for the insulator and doesn't crimp down nearly as far as the other side. If you put the terminal in backwards, you'll end up with a really lose crimp that will not hold the wire.That isn't revealed in the instructions, but in my first attempt to use the crimper, I put the terminal in backwards and got a bad crimp. But it was obvious that something was wrong because the insulated end was smashed down and the terminal end was hardly crimped at all. It didn't take long to figure it out.I suspect that people who are having trouble with this tool are just putting the terminal in backwards.My first usage was with insulted connectors and they were a little loose. After some inspection I realized there is a front/back, correct/incorrect way to crimp these insulated connectors with the Astro 9477. My old crimpers there was no right/wrong way, just put them in and squeeze. On each half of the 9477 die set there is a split front to back where one half crimps tighter on the copper wire itself and the other half crimps looser over the insulated wire. Inserting the connector the wrong way results in a loose crimp around the copper wire which is where you want the tightest crimp. My old crimpers applied the same crimp on both the wire and insulation so I never gave it a second thought these new 9477 crimpers were different. THEY ARE so pay attention. The side of the dies with the painted dots is the side with the looser crimp for the insulation half, so put the connector all the way through from this side. Basically they are making 2 crimps at once. The open barrel/D-sub and open barrel terminal also have dies which exhibit this split, dual crimping capability so pay attention when inserting the connectors for those as well. For someone who does allot of crimping with these dual crimp connectors the 9477 could be a real time saver.Please excuse my naivety if this split die scenario was obvious to others, but from comments that I read, I wasn't alone in initially using the dies in reverse fashion and getting loose crimps. Again, please ignore if you have already been using them correctly.Nothing much else to say other than when used correctly there is no way any connector is coming loose.kdGreat crimper that has nearly everything I was looking for. The crimp is adjustable and can be released in case of a jam/problem. I am quite surprised by the quality of the crimp, using the cheapest no-name ferrule at hand. I had to turn the adjustment wheel a notch to get there. I wished it had finer adjustment but the final crimp was totally acceptable.Sadly the instruction manual is quite minimal, anyone that want to make good crimp should refer -at a minimum- to a visual crimp inspection guide. In a nutshell the strand should be slightly deformed so that there are no airgap but not too much to a point where they would break-off.I wouldn't use them to build an aircraft or a race car -that's what the more expensive certified crimper are for. I'll use them to wire an electric motor to my kayak and wire a couple of relays for a future hydroponic system. I'll be using Raychem terminal for the high power stuff. Especially if I need to splice them.Not the cheapest, but still much cheaper than other options. Quite happy with it. It saves a lot of space. The crimping die are very very easy to use. Only issue is there should be more instructions on what die is used for what.I LIKE IT BUT WHEN CRIMPING SMALL BARE CONNECTORS, I FIND THAT THE CONNECTION COULD BE TIGHTER. I TRIED ADJUSTING THE TOOL BUT YOU CAN PULL THE CONNECTION APART WITHOUT A LOT OF PRESSURE. BUT ON MOST CONNECTORS IT DOED A GOOD JOB.I have only used it once. It seems to work well. I will update later, if I have a problem. I will report back.Over all good tool but cheaper finish as to be expected. Ideal for mechanics own use, wouldn’t recommend for a shop tool