Good condition, 6,5/10, very worn and dirty, some cracks in the plexi front and a small piece missing, shadow in the tolex from the letters R S on the side from a previous owner (Rod Stewart? Just kidding.or?), this is a very rare amp from the very earliest days of Orange UK, the cream colored crest logo is the giveaway that this is an ORS100 as the GRO100 and OR120 both have black crest logos, the black bracket by the input jack is according to some a sign that this amp was made by legendary Matamp (Mat Mathias in Huddersfield, UK) even though the official break between Matamp and Orange happened in 1971 but most believe they kept making some models until the mid 70 s, the sound is a very brittish and reminds us of a mix of 100W Marshall with a cleaner Vox AC30, the knobs are left to right: 1. FAC-knob; Frequency Adjustment Control (EQ-knob)http://orangeampguide.atspace.com/FACknob.html2. Bass3. Treble 4. Presence5. Volume. We have had it checked thoroughly by our amp tech and he cleaned it up internally but since everything works well and measures OK he decided not to touch anything after removing oxide, bias was set well for the exisiting tubes so no bias trimmer neededThe number on the back panel is #OA7121 and it is unknown what this number means, but the hand written number 9102 dates this amp to 1972