Replacement lamp

The lamp you received is correct. I own a lamp replacement company. It may of been pakaged incorrectly or maybe you received just the bulb and not the housing or vice versa (housing included). First, unless housing is damaged NEVER buy a new one...just the bulb will do. Housings are the biggest markup on replacement lamps. They are manufactired at a low cost and usually retailers drive up the lamp price because they include an uneeded housing. The bulb itself (XL-2100U) should be a round bulb. Check out my listing and compare this to what you received:
http://rearprojectionlamps.com/2000u-lamp-p-2277.html