The new stoppers have an ergonomic grip that makes the opening and closing of the flasks easier and more secure. The tapered bodies of the stoppers have moulded ridges for optimal flask sealing. Coloured inserts in the different sizes of stoppers allow the easy identification of the corresponding ground (NS/TS) neck size. The colour identification system used for the inserts is identical to that used for the KeckTM interchangeable glassware clips.
| 29 205 02 01 | 7/16 | blue | 28 | 10 |
| 29 205 03 04 | 10/19 | green | 32 | 10 |
| 29 205 04 07 | 12/21 | violet | 35 | 10 |
| 29 205 06 04 | 14/23 | yellow | 38 | 10 |
| 29 205 07 07 | 19/26 | blue | 42 | 10 |
| 29 205 08 01 | 24/29 | green | 46 | 10 |
| 29 205 09 04 | 29/32 | red | 50 | 10 |
| 29 205 11 03 | 34/45 | orange | 54 | 1 |
| 29 205 12 06 | 45/40 | brown | 60 | 1 |
