Rigid Contact Lenses, Gas-Permeable

Immediate comfort
Free single-use trial lenses (Red tint)
Guarantee of fit (3 months)
Available in different materials
Deliverable in 72 hours
Irregular cornea
2 years
Daily wear


BioFlex S2, rigid gas permeable contact lenses with multi-curve geometry featuring softening of the junctions and a tapered perfectly rounded edge. Thanks to technology the BioFlex S2 has a design that offers maximum comfort to the patient.


Start with :

Examination in biomicroscopy
Keratometry and/or corneal topography

Choice of lens diameter (ØT)

The diameter of the first trial lens is limited to that offered in the trial box (9.20 or 9.50), unless you order a custom-made trial lens, in which case the choice will depend on the corneal diameter (ØC), corneal toricity (AstC) and palpebral opening:

Corneal diameter  : Ø= ØC -2 
Corneal toricity  : 
AstC˂ 1.50 D → ØT ≥ 9.20
AstC˃ 1.50 D → ØT ≤ 9.20
Palpebral opening :
Large Diameter for snapping fit
Small diameter for inter-palpebral fit

Choice of radius of curvature (r0) 

The choice of the r0 of the first trial lens depends on the corneal toricity:

K-K’< 0.3 mm to r0 = K-0.1
K-K’> 0.3 mm to r0 = K-0.2

Evaluation of fit

After fitting the trial lens, wait 30 minutes before proceeding with a fit assessment.

Ideal fit
BioFlex S2 Alignée
Centered lens
Homogeneous fluorescence
Alignment ring
Peripheral clearance band from 0.5 to 0.8 mm
Movement of 0.5 to 1 mm after blinking

A fit assessment always begins with an observation of the central zone

1 – Central zone (Static observation, lens centered)

Tight Fit

BioFlex S2 serrée de 0.2
Excessive central fluorescence
Air bubbles
Lens off-center and low
Reduced mobility

Possible solutions  : Try a flatter radius

Poor Fit

BioFlex S2 Plate
Large central contact area
Lens off-center and high
Excessive mobility

Possible solutions  : Try a tighter radius

2 – Centering and mobility

The evaluation of centering, mobility and periphery should only be done after finding the r0 which gives the best alignment in the center.

Centering (static observation):
BioFlex S2 centrée

The lens must be centered; a shift lower is tolerable as long as the lens does not cross the limbus.

Lens off-center and low : choose a larger diameter by 0.3 to 0.5 mm
Lens off-center and high : choose a smaller diameter by 0.3 to 0.5 mm
Mobility (dynamic observation)

The lens should exhibit slight movement after blinking, with the lens moving up, then slowly refocusing.

3 – Periphery

Trial BioFlex S2 lenses have a standard peripheral clearance (d). Depending on observations it can be adjusted by ordering a tighter or flatter clearance.

AEL SERRE - Choisir d+
AEL TROP OUVERT - Choisir d2-
Wide clearance: (>1mm) will cause excessive lens mobility and formation of air bubbles in the periphery. Choose a tighter Edge-Lift (d-, d2-, or d3-)
Fine Clearance: (<0.5mm) will result in reduced lens mobility. Choose a flatter Edge-Lift (d+, d2+, d3+ or d4+)


Perform an over-refraction to determine the power of the final lens.
Start by looking for the best visual acuity with only spherical power, then compensate in the cylinder.
If the refractive astigmatism is less than 0.75 D, it is better to disregard it, and order a spherical BioFlex S2
If the astigmatism is greater than 0.75 and the gain in acuity is significant, order an external toric lens: BioFlex S2 TE

Internal toroidal fit : BioFlex S2 TI

When the corneal astigmatism exceeds 2.50 diopters, the lens is unstable and the fluorescent image is not satisfactory, in this case the best solution is to change to internal toric lens: BioFlex S2 TI.
For fit, send the Keratometry (or the topography) and the glasses correction to the lab. We will send you a definitive lens with an exchange option.
BioFlex S2 sphérique sur cornée torique

Spherical lens on a cornea with high toricity 

BioFlex S2 TI (Adaptation légèrement serrée)

Internal toric lens on a cornea with high toricity


Radius of curvature  6.50 to 9.00 mm by 0.05
Diameter 8.00 to 12.00 mm by 0.1
Peripheral clearance per 0.03 mm Standard : d
Slow (tight): d-, d2-, d3-
Quick (flat): d+, d2+, d3+, d4+
Sphere +30.00 to -30.00 D by 0.25
Cyl Up to 6.00 D by 0.25
Axis 0° to 180° by 1°
Addition  Up to 4.00 D by 0.25


Classification Focon III 4 Focon III 4 Focon III 5 Focon III 5
Name Roflufoco C Roflufocon Roflufocon Tisifilcon A
DK 65 100 125 180
Hardness 79 75 77 81
Light transmissibility 96% 97% 94% 96%
UV Filter Yes Yes Yes Yes
Tint Blue/Red Blue Blue/Grey Blue



We recommend using a care solution for rigid contact lenses without preservatives Regard K®

See product




Biolens Lab offers a 3 month guarantee of fit for BioFlex S2 contact lenses