You are purchasing the KNIFE (4 arms) and you will receive with it the bolt, 2 small washers and 1 large washer with square hole. The blade hole is a round hole by design. This is because of our intentional slippage feature for safety. The blade (aka knife) is sandwiched in between 2 of these large washers with square hole. The shaft has a square end profile which holds the large washers in place. You will receive a new bolt. For installation, please call to discuss. Installation is done at the customer's own risk and Alterna Jar LLC does not assume any responsibilities over a self-installed blade assembly and whether or not you are able to do the job "correctly and appropriately". You need your own tools and the torque understanding. Keep in mind that the bolt is "LEFT" threaded, which means "LEFTY- TIGHTY and RIGHTY - LOOSEY" (turn left to tighten and turn right to loosen). Also keep in mind, wear gloves and eye protection, because the knife edges are "SHARP", not razor sharp, but sharp enough to cut your hand / fingers etc. Also, un-installing your previous knife from your blade assembly could loosen up the bottom gear piece, the other end of the shaft.

Be aware that you could damage it when holding the blade assembly in a vice or vice type tooling. Also, how do you know that your blade assembly bearings are still good? Examine them. If you feel any rumbling or unevenness when turning the blades, or you see brown dust on the bottom end, the bearings might not be good anymore. That said, not that you are obligated, but we encourage you to call us and we certainly discourage you from undertaking this blade switch. However, if you choose to buy the knife, you understand that you are hereby responsible, accountable, and liable for the job and what may follow, and not us. 801-623-3225 - Call!

Note: This KNIFE DOES NOT fit and/or work on blade assemblies in the Blendtec Wildside or Fourside, or any other Blendtec type jars, or any other blade assemblies and/or blender jars, as a matter of fact. Don't try it. It does not work. Don't make me explain why.

The bearing housing and gear / shaft is NOT part of this Knife / Bolt / Washer purchase. Note, you have already 1 of the large square-hole washers. Also, you already have 2 small washers, we are sending you 2 new ones and 1 new bolt.