The classic production 1133B that is commonly reffered to as the "Steve McQueen". This is the most common variant, although it is also the most in demand. It has a matt blue dial (two different shades to to different dial suppliers) as opposed to the metallic blue of the 1133B transitional and chronomatic version. Like all vintage Monacos, seal melt is the enemy. Is there a black goo visible under the crystal or worse still has some seaped onto the dial? Actual paint peel is also an issue that can be left behind from past seal issues that have been resolved. Also hands. A high percentage of models on the market have service hands (originals replaced by service departments over the years). Service hands are similar but have less aged lume and often don't match the hour marker lume. Watches with service hands are worth less (how much less is open to personal preference and debate!). Movement can be calibre 11 or 12. Note on calibre 11 models the date wheel can need attention and occasionally these stick. Check for serial number and model number stamps between lugs, some have been polished off by service departments, but some can be difficult to see.