The key decision maker is the throughput. This means how many samples you analyze at the same time. You can select the model 310 (single-capillary = 1 sample „at a time“), 3130 (4 samples at a time) or 3130xl (16 samples at a time). These sequencers are no longer available new, only refurbished. Additionally you can think of 3500 (8 samples at a time) or 3500xl (24 samples), this is the newest series, and last but not least 3730 (48 samples) and 3730xl (96 samples). We do offer service, application support, upgrades, reagents and consumables for all of them.