There are a few things you should know about bicycle handlebar extensions, bend style, fastening styles, and construction techniques.
The majority of mountain bicycle handle bar ends are made using a process called TIG (Tungsten Inert Gas) welding, this allows the builder to join two pieces of metal with exactly the same alloy, of the same metal, making an incredibly strong joint. The alternate method of fastening the pieces of bar ends together is called bonding. This uses an epoxy adhesive to join the parts together.
There are two ways bicycle handle bar ends are fastened to the bicycle handlebar. The most common is the cinch style. This involves the use of a cast aluminum clamp, or a small piece of tubing around the handle bar that has fittings, like a stem, to draw the bar end cinch piece tight to the handlebar. Cinch styles require, and use, a steel bolt to tighten them. The other, less used, style of fastening is "wedge style", this is the way stems fasten into mountain bicycle fork steerer tubes. There is a cut wedge of metal that is threaded, which slides against another incline plane cut on the bar end itself. As the two slide against each other, it produces a greater circumference, and expands against the inner diameter of the handlebar. Occasionally there are handlebars that have a broader inner diameter than the wedge system can accommodate directly. In these cases you get the next larger size of the bar end that will fit your bar, or in some cases an aluminum tube cut lengthwise is provided to slide over the wedge assembly to act as a shim. The shim system is quite satisfactory, and produces a rigid grip on the inner mountain bicycle handlebar.
Many, but not all, of the mountain bicycle bar ends we sell, come with tubing end plugs, so dirt won't get into the handlebar or the bar end. It also keeps you from serious injury through an accidental Biopsy procedure. When the handle bar ends come with end plugs, we say so. In a few cases, rubber hoods, or boots, come with the bar ends to cover the entire cinch area, which also closes off the end of the handlebar.
Bicycle Handlebar extensions come in three styles of bend, Straight, Ski, or "L" bend. The straight bar end has the grip tube as a straight piece welded at an angle onto the fastening assembly. This was the first style made. As things became more sophisticated the Ski and L bend followed. The "L" bend has the grip tubing bent in the middle and welded, at a slight angle, to the fastening assembly, generally flat with no upward bend at the tip of the bicycle handlebar extension and offer 2 hand positions. The "Ski" bend has the grip section placed at a slight angle to the fastening assembly with an upward bend, at it's end like a ski tip, so there is a vertical grip surface.
The part of the bar end that fastens to the handlebar, everything but the tube you rest your hands on, we refer to as the "fastening assembly, "cinch assembly", or "wedge assembly". In the case of the cinch style bar ends, the cut steel tube that slides over the handlebar, and clamps to it we refer as the "cinch tube". The threaded piece that recesses the bolt head and provides the threads to draw the cinch assembly together, we refer to as the "cinch fitting".
The tubing welded the fastening assembly that your hands grip we refer to as the "grip tube". L-bend style bar extensions use one, or sometimes two pieces of tubing in making the grip tube. To describe the grip tube from the fastening assembly up to the first bend, we refer to it as the "primary grip section". To describe from the end of the first bend to the end of the grip tube, or up to the second bend we refer to as the "secondary grip section". If the extension has a second bend with grip tubing that extends beyond it, (Profile XC Sierra Long, Answer XC Guardian), we refer to this grip area as the "tertiary grip section".
There is a bar end feature you are likely to hear more about, and it's being called a "low profile" design by many bar end makers. The theory is making the grip tube narrower at the cinch assembly allows the maker to use a narrower cinch assembly piece to reduce the total weight of the bar end while providing the maximum room for your hand on the bar. The "low profile" design has its detractors. Thin wall and tapered wall handle bars have very little tubing wall thickness at their very ends, a narrower cinch assembly increases the cinch clamping pressure and stress in use on a smaller handlebar surface area. Also, as all geometry students know, some of the base stability gained in using the cylindrical shape of the tubing is lost when the base is made narrower. In the case of low profile handlebar ends this means there is a possibility of side impact failure below the stress failure levels of bar ends that are not "low profile".
The measurement of the angles of bend for these bar ends was measured using the Pro SmartLevel¨ from Wedge Innovations in Sunnyvale, California. The Pro SmartLevel delivers a digital reading accurate to the tenth of a degree, which will be more accurate than most welding jigs can reproduce, so there may be slight variations in any specific pair. The work was done over many days, if there has been any mis-reading, or mis-calculation of angles, we apologize to the manufacturer in advance.
Many of the American made bicycle handle bar ends use the same press-in grip tube/handlebar end plug. Molded with reinforcements, it's made of Black plastic, this is the Rodon end plug being sourced through Out Water Plastic in Woodridge, New Jersey. This plug is well suited for this application, because of its strength, while being very lightweight. Each of these Rodon plugs weighs 2.63 grams.
All handle bar ends have been weighed from production models, to 1/4 gram resolution, no matter what a maker says, these are the real weights. The choice of whether to image (photograph) a right or left hand version of the bar end, because I am a leftist, was purely political.