The Coleman Vacu-Print™ Long Chamber is used for processing large evidence, such as, rifles and bats, or if larger quantities of evidence must be developed. It is 48" long and has a 7 3/8" inside diameter. It comes with a plexiglass stand. The Pump/Motor is 1/3 horsepower with 3 CFM vacuum. The same pump/motor will operate either chamber. It is possible to purchase both chambers and only one pump/motor. Store each piece away in a closet or cupboard until needed.

To use the vacuum system with either the table top or long chamber, place several items inside. They may touch the sides of the chamber and each other. Cut a small strip from a Hard Evidence™ pouch and tape it to the inside of the chamber or put five to ten drops of liquid glue in a small dish and place it inside the chamber. Evacuate the chamber and allow the items to fume under vacuum for about twenty minutes. When finished, the evidence will not have a thick layer of white powder residue, although the latent prints are "locked on" the item. Allow them to remain in the air for about ten minutes before processing them with powders or chemicals.

If a forensic light source or ultraviolet lamp is available, it is recommended that fluorescent dye staining or powders be used to visualize the latent prints on these pieces of evidence. If the evidence is fairly fresh (within about a week), use fluorescent powders, such as Redwop™ and Greenwop™ or Blitz-Red™ and Blitz-Green™ magnetic fluorescent powders. If the evidence is older than a week or so, liquid dye staining is recommended. Some of the liquid dye stains available are Ardrox, Rhodamine 6G, and Basic Yellow 40.