Original sentence: ERS instruments from ETC, Altman, Selicon and a variety of others have interchangeable barrels which can both create a very sharp or very soft beam as well as alter the beam degree, which can range from a narrow, long distance 19-degree spot to a broad and short-distance 50-degree or even 90-degree.Since its introduction many other manufacturers have introduced their own 90-degree barrels.The first 90-degree profile latern was developed by Selecon Performance Lighting as part of their pacific range of products
Edited sentence: ERS instruments from ETC, Altman, and a variety of others have interchangeable barrels which can both create a very sharp or very soft beam as well as alter the beam degree, which can range from a narrow, long distance 19-degree spot to a broad and short-distance 50-degree or even 90-degree.Since its inception many other manufacturers have followed suit.The worlds first 90-degree profile latern was developed by Selecon Performance Lighting as part of their inovative  pacific range