One of the more frequent questions asked seems to be which Speedmaster Professional is which. This table attempts to answer that query.

Current/Recent/Upcomming Speedmaster Professionals:
Ref. #	Case	On	Description	Calibre	Crystal	Caseback	Availability

Non-Moonphase Models:
3570.50.00	Steel	Bracelet	“Moonwatch” model as used by NASA	1861	Hesalite	Steel	Yes
3573.50.00	Steel	Bracelet	Both crystal & back are Sapphire replaces 3572.50.00	1863	Sapphire	Sapphire	Yes
3572.50.00	Steel	Bracelet	Discontinued Old Model Hesalite Crystal Sapphire Displayback	1863	Hesalite	Sapphire	Discontinued
3578.51.00	Steel	Bracelet	Snoopy “Eyes to the Stars” 5,441 piece Limited Edition (L.E.)	1861	Hesalite	Snoopy Sapphire	Limited/Sold Out *
3569.31.00	Steel	Bracelet	35th Anniversary 3,500 piece L.E.	1861	Hesalite	A11 Sapphire	December 2004
3570.40.00	Steel	Bracelet	Red/Orange Dial, 2,004 piece L.E. Japan only	1861	Hesalite	Steel	Japan 2,004 pieces
3570.31.50	Steel	Bracelet	Black on White Mitsukoshi 300 piece L.E. Japan only *	1861	Hesalite	Steel	Sold Out*
3873.50.31	Steel	Leather	Black Leather non-ridged strap version of 3573.50.00	1863	Sapphire	Sapphire	Yes
3870.50.31	Steel	Leather	Black Leather double ridge strap version of 3573.50.00	1863	Sapphire	Sapphire	Yes
3195.50.00	Y.Gold	Bracelet	Yellow Gold on Yellow Gold Black Dial	1863	Sapphire	Sapphire	Yes
3195.59.00	Y.Gold	Bracelet	Yellow Gold on Yellow Gold Black "Apollo-Soyuz" Dial ¿L.E.?	1863	Sapphire	Sapphire	¿Unknown?
3695.50.31	Y.Gold	Leather	Leather non-ridged strap version of 3195.50.00	1863	Sapphire	Sapphire	Yes
Moonphase/Date Models:
3689.30.31	W.Gold	Leather	White gold on Leather strap	1866	Sapphire	Sapphire	Yes
3688.30.32	Platinum	Leather	Skeletonized 57 piece L.E. on Brown leather.	3604	Sapphire	Sapphire	Limited 57 pieces
3576.50.00	Steel	Steel	Black Dial Displayback Moonphase/Date on Bracelet	1866	Sapphire	Sapphire	Yes
3876.50.31	Steel	Leather	Same as 3576.50.00 except on black leather strap	1866	Sapphire	Sapphire	Yes
Professional X-33
3290.50.00	Titanium	Titanium	X-33 "Mars Watch" on Bracelet "Original Pattern"	1666	Sapphire	Titanium	Discontinued? ***
3990.50.06	Titanium	Kevlar	X-33 "Mars Watch" on Kevlar Strap "Original Pattern" **	1666	Sapphire	Titanium	Discontinued? ***
3291.50.00	Titanium	Titanium	X-33 "Mars Watch" on Bracelet "New Pattern"	1666	Sapphire	Titanium	Yes
3991.50.06	Titanium	Rubber	X-33 "Mars Watch" on Rubber Strap "New Pattern"	1666	Sapphire	Titanium	Yes

Notes:
*	This model is only available used as dealer stock has sold out. It is possible that this may also be the case with the Snoopy LE...
* *	Omega web page states "Rubber Straps" however watch is pictured on a Kevlar Strap... Very weird!
* * *	Model is still shown as active on Omega's site dispite the fact it's replacement model have been available for at over one year...

If you have updated information to add to this table, please contact the compiler. Special thanks to Birte and Tera Leung for their tracking down information on the 2,004 piece limited edtion Japan Only 3570.40.00.