Baker has approximately 24 Fresnel 9's (referring to 9 inch diameter), and 2 Fresnel 12's (lovingly referred to as ``trash cans''). These lights can be readily distinguished by the flat lens on the front that looks like a bulls-eye. The 9's are good for short distance work and all of them can be focused using a sliding knob on the bottom of the barrel. To replace the bulb, the lens is on a hinge. Pull up on the locking lever and rotate the lens towards you. Inside you will see the bulb. Press downwards on the bulb and rotate (sorry, I can't remember which way) after a 90 degree turn the bulb will be free (it is not threaded).
There are also a bunch of tiny fresnels that have occasionally been used as warmer lights, they are not good for much else, but I'm telling you that they exist just in case you think of some use for them.