R-R did not assign short style names for their wire markers such as P or B; any such letter names you see were assigned by SunsetRolls to assist you in recognizing each style. The markers were originally identified by numbers such as: E51070. There was often a different part number for each marker number of any particular style: an E51072 was a number 2 and an E51076 was a number 6. The part numbers for most styles were not so simple; in general, the last digit of the part number did NOT correspond to the number on the item. Most humans aren't good at differentiating such seemingly random, alphanumeric part numbers. Using them would make it rather cumbersome and confusing for our general customer. We have instead devised our own style names which are generally meant to be descriptive of the items they represent. Each of our style names refer to all items of a particular style no matter what numbers they might carry.

The basic marker is a style P, for plain. It has a number only, with nothing on its back side. A marker with a 'B' added on the back side is a style B; one with an 'M' is a style M.

A second and third character is added to the basic style name if needed. If the numbers are inside a small circle a P becomes a Pc or a B becomes a Bc. The small 'c' denotes a small cirlce.

Many of the cars used special hooks or, later, Ross Courtney connectors for spark plug terminals. On these cars the plug markers were closed on their bottom ends with a smallish 0.15" diameter hole for the wire strands, but not the insulation, to pass through. These styles we are calling 'blind'. The final letter 'B' in the style names BB, MB or BcB indicates a blind (closed end) marker and is not an indicator of a back side letter. These blind styles are only used at the spark plug ends of the wires.

Initially the Ghost markers were ignored since we lacked any information about them. We have since learned that there were several sets of part numbers for Ghost markers but the details and/or samples for most of them are not yet finalized. If you have visited our site previously, please be aware that the style designators for the early Ghost series markers have been recently changed (as of mid-August 2006). Sorry for any confusion, but we have new information that has altered our understanding about the earlier styles.

A special convention is used for most of the styles used on Ghosts: G#. Replace # with a letter a through z. Some of these styles may prove to be visually identical but, just in case, the capability for all to have unique designators exists without redefining the convention. It is believed that all of the G# styles were physically larger than the standard (0.40" x 0.40") styles used later. Even when a style, such as Gp, is used on later, non-Ghost models we will continue to call them by their G-series style name. The style P was first used on the later Ghosts so one could logically give it a G# label. But since style P had been previously defined and produced by us, and its dimensions are those of the smaller, non-Ghost markers, the P designation was retained to avoid undue confusion for us and our customers.

We use 4 distinct style names for the sleeves used on the 24 plug wires of a PIII. These sleeves designate the wires by cylinder bank (A or B) whether on the intake or exhaust side of the head (I or E) as well as which cylinder (1 through 6) of each cylinder bank. A PIII uses styles BE, BI, AE and AI all of which have a number 1 through 6 in combination with either an I or E (I2, E4, etc.) on their front sides as well as the letter A or B on their back sides. Actually each PIII uses two sets of each of these 4 styles for a total of 48 sleeves.

Style Z is a single, style P marker which carries the number zero. It was used on the coil wire of some cars although such usage was discontinued in the later years. When we first produced it, it was the only known marker to carry the number zero so a 'Z' designation seemed appropriate. We are no longer confident of such exclusive zero usage. Many Ghosts had a 'C' on their coil wire marker but the last Ghosts used the style Z instead which displayed the numeral '0'. In 1923, between the earlier 'C' coil wire markers and the later '0's, there was a a 1" long part number E17784 used on coil wires of series J-P Ghosts. This interim coil wire marker may have carried a 'C' although we feel it may have used a zero or possibly even have had a blank spot with no character at all. Whatever marking E17784 may have had we call it a style Gz which may, or may not, stand for Ghost zero. We have also found drawing references, but no instances of usage, for a zero numbered style Pc marker as well. Although there are 3 potential marker part numbers with a '0' marking, we will continue to apply the Z style designator to the E51070-like item.

Style S is an anomaly - it doesn't carry any markings; by the above conventions it would be a style __ (blank), not exactly easy to communicate. It came from a Springfield PI and covers a brass tab used for the spark plug terminal. The cylinder number is stamped into the brass tab and this marker style is a semi-blind sleeve covering most of the tab. Hence, we have style S for S(leeve).