This fuse holder has no markings. Its size puts it in the CD 687 range. I've spoken with Mr. N. R. Woodward about this piece, and he indicated that there have been some new CD assignments for fuse holders of this style since GIFONA was published, so if you purchase this piece you'll probably want to get in touch with him to pin it down or to get a new CD number assigned. This insulator is in VNM+ condition and a wee bit greener that it appears in the photo. 2 1/2" diameter by 4 1/4" tall, 4 1/2" wide at the arms. Quite a remarkable piece of glass, available for $125 postpaid to US addresses.